Your browser (Internet Explorer 8 or lower) is out of date. It has known security flaws and may not display all features of this and other websites. Learn how to update your browser.




Age of companies in S&P500

Pradeesh Kumar

​This model attempts to understand the behavior of average lifetime of companies in the S&P500 index. The reference mode for the model is a graph available at this link: (page 5) which was discussed in the System Thinking World Discussion forum.

Mergers & Acquisitions can be one of the reasons for older companies to be replaced with newer companies in the Index. With M&A of older companies, the empty slots are taken over by newer companies. However, overtime, these new companies themselves become old. With steady M&A, the stock of older companies decreases and stock of newer companies increases. The result is that average age of the companies in the S&P Index decreases.

The oscillations in the diagram, according to me, is due to oscillations in the M&A activity.

There are two negative feedback loops in the model. (1) As stock of new companies increases, the number of companies getting older increases which in turn decreases the stock. (2) As M&A increases, stock of older companies decreases which in turn decreases M&A activities.

Limits of the model

The model does not consider factors other than M&A in the increase in number of new companies in the Index. New companies themselves may have exceptional performance which will result in their inclusion in the Index. Changes in technology for example Information Technology can usher in new companies.


1. It is assumed that M&A results in addition of new companies to the Index. There could be other older companies too, which given the opportunity, can move into the Index. Emergence of new technologies brings in new companies.

Business System Dynamics

  • 5 years 6 days ago

Bottom-up Sales Forecasting

Kishau Rogers
Bottom-Up Sales Forecasting for Startups
The purpose of this simulation is to demonstrate the implications of forecasting sales without consideration for how much it cost you to acquire a lead and how much you have available to spend. A common mistake in sales forecasting is to define your # of expected sales leads based on your total market size and your assumption regarding the % of that market you can reach. 
This model demonstrates the forecasting impact to defining the # of expect leads based on how much it cost you to acquire a lead and how much you have available to spend. 
Important Variables:1. [UseLAC?] (set to 1 to use the lead acquisition cost to define your reachable market; use 0 to set the reachable market to equal the total available market size)2. LAC (should equal what it cost you to acquire a lead)3. SalesMarketingBudget : how much you have available to spend on customer acquisition
Other Variables:4. Price : Avg spending amount per new customer5. Total Available Market : Total available market size6. Conversion Rate : the % of your target market that will become a lead

Startup Business Forecasting Sales

  • 2 years 11 months ago

To Be Business and Technology Architecture

Lisa Martinez
Enables the different components in the 5 capability model in a visual manner for Enterprise and Business Architecture stakeholders.  


5 Capability Model
The 5 capability model has many stock and flow children which each organization will need to model based on their current state.  

  • Aligns to APQC Process Framework
  • Aligns to Principles in ISO 9001, 26000 and 27001 

Aligns Zachman Framework Enterprise and Business Architecture with Executive and Leaders from a business management level across any organization.  

A method in which to align and benchmark any organization or agency, with the system(s) logic required from Architects in Row 3, to enable Row 4 engineers who need to supply physics. 

Getting terms to align to the generic objects can be a trying task, unless you simply list the stakeholders "semantic" term below the stakeholder in the presentation layer by order shown in the business process management section above the capability management group.  

Business Technology Quality 5 Capability Model Application As Is To Be Enterprise And Business Architecture

  • 5 years 3 months ago

Multi-echelon Inventory Optimization

Girikanth Avadhanula
This is a multi-echelon inventory model and demonstrates the benefits of computing safety stock based on multi-echelon considerations rather than single-echelon calculations.The network is plant->stocking point-> Distributor-> Retailer. The mean demand of retailer is 100 and sd-30. Since the network has only one sp/one distributor/one retailer, the same demand propagates up (subject to inventory netting). You can do safety stock computations at distributor and SP based on the classical safety stock formula. Post that keep reducing the safety stock at the distributor and see if the service level is getting impacted. Do you think you can manage with SS less than what is given by the classical formula (applied at distributor and stocking point?)

Business Logistics Supply Chain

  • 9 months 2 weeks ago

OSCON 2017: Help Desk - True Cost Impact of Improper Escalation

Kishau Rogers
​The Problem: What is the true cost of escalating too many Tier 1/Level 1 tickets to Level 2/3 engineers?
Things to measure: How does this impact:1. (MONEY) Cost per incident - what does this cost the business? 2. (TIME) Service Level - how does this impact desired service levels/SLAs? 3. (PEOPLE) Agent utilization - how does this impact backlog? are we overworking engineers? Does this contribute to staff burnout?

Business Help Desk Technology

  • 2 years 11 months ago

Simple Retail Sector (tweaked)

Ash Moran
Original (more DYNAMO-like) version is here:

The Simple Retail Sector model from Section 1.7 of DYNAMO User's Manual by Alexander L Pugh III, which is adapted from one from Industrial Dynamics by Jay Forrester. (I bought the 5th edition without realising there was a later one, hopefully it's still the same model in there.)

DYNAMO Retail Business

  • 5 years 12 months ago

Online Shopping is Different from Traditional Shopping

Proff R

Online shopping is a fast rising field where many people are opting to buy products and items online instead of going to physical stores and malls. This is pegged on the rising use of smart phones that have sky-rocketed the field of ecommerce.

Many people have ventured online to sell products and services to clients who prefer shopping online. For example, with the onset of online stores, such as Amazon, many business people have come between Amazon and the consumer by writing product reviews and guides that have helped many customers to have a better understanding of the kind of products to buy and the products that meet their needs 100%.

The reviews of products as well as the pros and cons are exactly what customers will get when they visited a physical store or mall, including a product review site. This means that online shopping has become the next big thing!​

Business Finance Commerce E-commerce Online Shopping

  • 1 week 4 days ago

What facilities should a coworking space have?

Rahul SHarma
Coworking spaces are the next big thing as its trend is on the rise.  Coworking spaces are providing a new place to the remote professionals, budding start-ups and freelancers. Coworking spaces are membership-based workplaces where diverse group of professionals work together in a shared environment in a professional manner. Most of the start-ups, freelancers and remote workers prefer to work from home, but the home may not be a suitable place if they have to meet their clients or their start-up is growing. The main reason why these remote workers are switching to coworking space is the flexibility that it offers. Choosing a coworking space in Gurgaon can be a stressful task and when there are lots of options available, it becomes more difficult to choose the best one. However, an ideal coworking space should have certain facilities to give its members a comfortable and convenient work environment.1. High-speed internet connectivityThis is the most important facility that a coworking space should have. Everyone looks for a high speed internet connection when searching for an ideal coworking space. Since, most of the work is now done digitally; every member would require a fast wifi connection till the time he/she is at the coworking space to perform daily activities. 2. Proper seating infrastructureA coworking space should have a proper seating infrastructure to offer to its members. When a person has to spend his most of time sitting at the workplace, it is important that he has a comfortable seating. Choose some good quality of comfortable ergonomic chairs and desks in place of normal desks and chairs. It will not be only comfortable for the members but will also help them in maintaining a good posture. Also, the coworking space should have provision of private cabins as well as open spaces as some the members may require different seating infrastructure as per their needs.3. Cafeteria The entrepreneurs and freelancers are going to spend their most of time in the coworking space and may not be able to go home or out for break. So, it is important that there should be a proper cafeteria with good quality food where the members can eat and relax. The coworking spaces can also provide unlimited tea/coffee to its coworkers as a value added service. 4. 24-hour accessA 24-hour access is an utmost requirement for every coworker, which includes 24-hour access to services like air conditioning, wifi and others too. The coworkers may need to work at any time so a coworking space should be such that can be accessed at all hours.5. SecurityWorking in a safe environment is a priority for every person. Everyone will prefer a coworking space that has proper provision for security of the members. The coworking space should provide lockers to the members where they can keep their gadgets and personal documents safe. It should also have a fire alarm and CCTV cameras for proper surveillance. 6. Power backupsEvery minute is important for the start-ups and entrepreneurs. Make sure that the coworking space has proper power backup so that the work of members does not get stuck when suddenly the power is out.7.  Networking opportunities People will like to join a coworking space that organizes regular seminars and fun activities to promote interaction among coworkers. These events will give them a chance to increase their networking opportunities by interacting with other start-ups and investors. 8. Access to breakout spacesMany coworking spaces in Gurgaon, today, are providing access to breakout spaces. Breakout spaces are dedicated places in the office where members can share their ideas with each other, de-stress and relax. These places are not confined to cafeteria but can be in form of lounge and gaming rooms. So, the coworking space should have a gaming-ready station with good LAN connection. The gaming room should also have pool tables, gaming consoles and board games. 9. PrinterThe coworkers may require taking a print of their documents or important papers. So, the coworking space should provide a printer in every room that can be accessed by the members all time. 10. Projector and TV in networking roomThe members may require projectors or TV in meeting rooms.  So, it is important that the coworking space provides this facility in each networking room.These world-class facilities will make a coworking space a work oriented, fun-filled, and comfortable and an ideal shared space where the members can work freely and learn while they grow.

Coworking Business Entrepreneur .

  • 1 year 3 weeks ago

Role of Chabots in Transforming Business and Customer Experience

Luke Morton

Are you tired of waiting for telephone operators to assist you in shopping or making any other inquiry related to the brand? Do you want some automated process to solve all your concerns without waiting for long? Well, technology has made a major discovery in this specific area by the introduction of chatbots that are 24/7 automated assistance for its users.

One of the research study by Oracle has proved that by 2020, 80% of the companies are planning to use chatbots to offer smooth customer service and business growth. Another study conducted by Facebook states that 56%  of the customer prefer contacting customer service through messages rather than getting assistance via phone call. Businesses have taken this study seriously and by the implementation of chatbots in their software, they are ensuring that their clients get seamless assistance at any point of time.

Did you ever approach any best and professional essay writers in UK to buy essay? Have you observed the integration of chatbots on their website to ask couple of basic questions and guide you with approaching the writer that suits you best? This is how chat-bots helps in providing assistance to customer so that they would be completely satisfied with your services.

What exactly is a chat-bot?       

To put in simple words, chat-bots are software integrated on brand’s websites or application that can talk with humans through live chat at any point of time. There are two type of chat-bots

1.     Simple Chat-bots:  Simple chat-bots work by answering the customer query by replying with pre-packaged answers. It scans through the keywords mentioned in the query and then reply with the answer according to that keyword. 2.       Artificial Intelligence – powered Chat-bots:  Chat-bots powered by artificial intelligence are more professional and natural-like. They answer the customer’s query in a more conversational tone and also understand the customer’s information to offer personalized experience.


Here are some of the way that chatbots help in enhancing customer experience and boost business growth.

Seamless Live-Chat and 24/7 customer service

Since every chat-bot operates in the same way as a person would communicate with any customer support employee, it replies to each customer with the best possible answer that meets their needs, that too in a conversational tone.

With the help of analyzing keywords and in customer’s query, chatbots deliver responses through a live chat with the software integrated in company’s website or application. So, customers will be no more in trouble to search through companies customer support employee online and ask them questions.

Do you often feel that you need to ask some urgent queries to customer support staff but it is their off day? Well, chatbots have made it convenient for you to approach the 24/7 seamless service even when the representatives are unavailable. So, there is no more waiting of email replies and voice messages, as chatbtos will not only deliver best solutions to the clients, they also promises to provide the feeling of chatting with live customer service operator.

Less IVR-induces Stress for Customers

Have you ever experience the long waiting times in an IVR (interactive voice responses) when your call is transferred to your desired destination department through a long process? Such systems ask multiple questions or require some transferring number to be entered to transfer to the support staff and even then you have to wait in case of multiple calls on line.

Chatbots have been able to provide stress-free and quick service to the customers by either providing an appropriate answer or lead them directly to correct human representative. In fact, in one of the recent surveys, it has been found that 70% of the customers would prefer using chatbots to get their tasks accomplished through a rapid and streamlined process.

Personalized Customer Experience

Since every customer would love to have a personalized assistant throughout the purchase journey and even after that, chat-bots have been designed to have capabilities to offer pre-purchase guidance to post-purchase customer support.

Once the company is able to achieve this goal, they not only leave a good impact to their customers, they are also successful in building a strong customer base where their clients will look forward to keep coming back to their clients.

Facebook ads Can Be Powered By Chatbot Technology

Chat-bots allows users to directly view the chat window in Facebook messenger, upon clicking up the ad, rather than sending your potential clients to your home page or application. Since you have already acquired each user’s insights and information, you can even personalize your ads to convince the potential clients from the very first impression.

Upon gaining good understanding of your target audience, you can reach out to your potential customers and there are higher chances that they start interacting with your brand’s bot.

With the services offered by chatbots mentioned in this article and countless other capabilities, it can be efficiently used by companies to enhance their customer service experience resulting in business expansion and growth.



  • 1 year 4 days ago

Instagram tips to build business

javaid hassan
Keeping your Instagram occupied is an extraordinary method to fabricate your following. A functioning record is more fascinating than an idle one. What's more, utilizing Instagram to impart a wide range of substance to your group of spectators in various organizations makes them much more intriguing than if you just offer one sort. On the off chance that you are online business advertiser, at that point you have better thought in the state of instagram and that is the more fruitful than different business apparatuses, and can get here the best site to buy instagram followers.Demonstrate multi Day in the Life
One of the extraordinary employments of Instagram stories is to take multi day and show up a couple of various occasions of the day to share what you are doing as it identifies with your group of spectators and your business. For instance, on the off chance that you are a business mentor, you need to impart your business and collaboration to other people.
Go straight
Take some time every day to go live, even simply sharing the energizing news. When you live by arbitrarily, your group of spectators will be informed on the off chance that they sign up. They will give close consideration to you and may even lament on the off chance that they pass up survival, however on the off chance that you leave it they will at present observe the chronicle.
Give sneak lookMake another item or administration? Give a sneak look about it. Evaluating another product that you might want to prescribe? Make a tale about it. The more reasons you can discover in the accounts, the better your quest for adherents will be.
Casting a ballot
Instagram gives you a chance to do surveying, which is a decent method to comprehend what your group of spectators is thinking. Keep the pool straightforward to stay away from any disarray, as these pools are not logical. On the off chance that you need the correct outcomes, think about confining the choice.
Exchange Instagram Stories for multi Day
In the event that you have an accomplice who serves a similar group of spectators as you, you can exchange Instagram for multi day. You run their accounts, and they drive you. This is an astonishing method to get cross advancement and more adherents.
Check to begin
In the event that you have a dispatch or a program coming up, use Instagram Stories to commencement to the dispatch. This is a fun method to get everybody amped up for your new advertising.
Use stickers and embellishments
With Instagram you have approaches to grab the eye of your group of spectators. Use them. Include embellishments, use stickers and include magnificent hashtags. Call the opportune individuals. Acclimate yourself with making up for lost time with devotees who like you. When you share a story, consistently make sure to incorporate the suggestion to take action. On the off chance that you don't let them know, your group of spectators won't work (or just once in a while). At whatever point you make any substance, you should recognize what your group of spectators needs to see subsequently.

Instagram Tips Business

  • 7 months 3 weeks ago

5 Technology Advances That Have Helped in Enhancing Customer Experience

Luke Morton
While every business is seeking to implement strategies to provide their customer best experiences and complete satisfaction, technology is playing a vital role in helping businesses do so. With countless technology innovation emerging in the market, almost every business is benefiting from the efficient and time-saving tools resulting in growth in productivity and smooth operations.

Although the major focus of every business is to provide seamless experience for its clients, the important thing is to make that experience effortless and time-efficient for them. From promising 24/7 customer support to offering product delivery and bill payments at door step, technology has come a long way.

As far as customer satisfaction is concerned, the main objective doesn’t only revolve around having optimized customer support, the systems must be competent enough to add human element as well as process automation. Although students who get help for assignment writing services in UK and for their technology and business related projects might get some useful information on emerging technologies, this article will also be a good read for future marketers and business owners to make their customer satisfied and contended.

Let us a take a look at 5 major technology advancements that has completely revolutionize customer satisfaction in business domain.

Virtual Reality

Since virtual reality has already entered the various fields in the society, its contribution to business is outstanding. Providing the immersive experience for users to experience almost anything they could have imagined, virtual reality has become a complete game changer for most businesses.

While businesses are looking for integrating new and innovative technologies, the use of virtual reality would help in their business rapid growth and productivity. If you ever got a chance to buy essay online, cheap and high quality services offer professional writers that can provide you with in-depth analysis of virtual reality and its role in modern businesses.

Some of the common applications of virtual reality in enhancing customer experience are as follows:

1.       Gamification

2.       Product simulation

3.       Hands-on demo or try before you buy system

4.       Virtual e-learning

Artificial Intelligence

While the development of machine learning and cognitive computing emerging in businesses, artificial intelligence is also contributing in playing a significant role in enhancing customers experience. AI functions in various ways including automation of customer support system, personalization assistance to customers, improved security services, e-commerce industry and many others.

Some of the brand like Netflix and Amazon collect and analyze their customer’s data that include search and purchase history and come up with valuable recommendations for users that they appreciate the most.

1.       Here is a list of some other ways AI is contributing to improve customer experience

2.       Improvisation of Contact Centers

3.       AI helps centralized customers data and connect each touch point for seamless accessibility

4.       It identify and analyze customer patterns and preferences

5.       It boost e-commerce industry

6.       It offers personalized experiences


With the integration of chatbots in brand’s websites and applications, customer have not only experienced seamless live chat and answer to all their queries, it has also contributed in building a string customer base towards the brand.

With the automated customer services, users no longer have to wait for any customer support staff availability, as the smart chatbots will help them with their queries at all times. The simple chatbots have been designed to have pre-packages answers and they deliver those answers by judging the keywords in the customer question.

Furthermore, AI used to enhance customer experience also boost employee productivity as employees can now focus on other important areas rather than receiving customer calls and talk about same things every day.

Chatbots can also be used to power Facebook ads as brands can directly open up the messenger chat window upon clicking on the ad. As this social media platform can collect and analyze customer insights, the data can be used to provide personalize recommendations and offer related to your brand.


IoT (Internet of Things)

Since IoT is another game changer when it comes to business and customer satisfaction, it is already contributing to meet customer’s needs and improve their experience. From sensors being used in smart gadgets and other devices, it has become extremely convenient to have communication between your IoT devices and make the processes efficient and time-saving.

Since IoT can gather massive amount of customer data, it helps in gaining customer insights like their preferences, changing behaviors, and device performances. This gather information can be used to work on areas that need improvement and development of more robust products.

Hence, if you already run a small business or planning to start one, make sure to make the most out of these advanced technologies if you want your customer to be satisfied and contended with your services.


Business Finance

  • 1 year 2 days ago

9 safety tips regarding rideshare business, rider, driver and their experience

Malik Nauman
1) Maintain Vehicle as hygienic as feasible

A hygienic car travels a stretched way. Riders anticipate the vehicle they chink to be principally immaculate. Grasp yourself to a definite standard of sanitation when managing your rideshare vehicle. Do not sway out of bed and into your vehicle appearing like a muddle. Maintain the inside of your car neat as a new pin. That means wiping down the door interiors and windows both exterior and in the interior as well as vacuuming the seats and floors. Obtain usual car washes to maintain the outside of your vehicle acceptable. Throughout the winter months, when city streets are sheltered in snow and salt, riders may be extra merciful of a somewhat filthy outer surface.As a replacement for forever staying in hotels, a lot of people choose for Airbnb accommodations. Coworking places are popping up in a lot of cities around the world. Attire services like Rent the Runway permit clients to rent out clothes for particular occasions as a replacement for having to crust out plenty of money to buy them.

This sharing financial system is also building a gigantic bang on haulage. A lot of people are opting for ridesharing services as a replacement for owning an additional car. They merely unfasten an application on their smartphone and pertain for a ride from an Uber or lyft driver. A little minutes afterward, their ride appears, and they obtain where they necessitate to go. There is no hassle about parking. Riders do not have to be bothered about a congested bus. They merely acquire individual transport services, every time they are required.

2) Take a seat in the Back Seat

If you are wandering alone, forever prefer the back seat. Many of the incidents that we have observed to have occurred  to passengers sitting in front.

3) Confirm Your Driver’s Rating

At the same time as equally Uber and Lyft keep an eye on a driver’s rating, for all time ensure that your driver has previous experience and a rating of above 4.5. If the rating is anything below that, drivers can get fired or deactivated from Uber or Lyft.

4) No need to Pay by Cash

A driver should never request you to recompense cash for your ride. Nowadays both Uber and Lyft offer you an alternative to tip subsequent to your trip, so there is no requirement to have your wallet out during a rideshare.

5) Be acquainted with Your Surroundings

If you are in an unknown city or area, ensure to follow your route on your individual maps application to make sure that the driver is following the accurate route. In addition to, if you are getting picked up from the airport, forever make sure to pursue the impelled directives when you unfasten the rideshare application.

Within the ridesharing financial system, any person who meets the baseline experience can initiate earning money all the way through driving. In addition, driving for Uber, Lyft, or several other transportation network company (TNC) can be incredible to decide to do on a notion.

6) Do not run after Surges

The principal draftee blunder that drivers put together is to run after down surges. Even though it may appear like an enhanced initiative in the diminutive run as of the advanced multipliers, chasing down surge charges will guide to disenchantment if there is no approach implicated. When a person intermittently run after surges, it is probable that the multiplier will fade away as that arrive. TNC surge algorithms are vigorously varying every minute, so running after multipliers one at a time is not going to facilitate you to earn money.

7) Plan Out Your Drives

The most excellent rideshare drivers have an delineate of what they are doing in progress. One of the main striking advantages of rideshare driving is having the capability to situate your individual schedule. It is preeminent to be acquainted with when your finest and most horrible times to drive are so that you can make preparation around somewhat else you have available on in your life.

Some people arrange merely a small number of hours in advance. Each and every city is dissimilar, so it is vital that you make out when traffic is profound and when surge charges are at their peaks.

8) Join Driver Communities

Drivers who converse with one another typically have the superior hand over a driver who is inaccessible from other drivers. By leveraging the influence of the crowd, you can become skilled at a faster pace and have a superior pulse for what is obtainable in the city.

Connect to Facebook groups and additional online communities. There are more than 150 driver groups all over the country on Facebook, which includes together US groups and city-specific groups. Text groups in applications like whatsapp and groupme can also establish constructive to novel and expert rideshare drivers in a similar way. Online forums for example uber people are a grand place to seek out answers to the majority of your rideshare questions. You should also connect with a number of blogs and vlogs, which includes the rideshare guy, the straightforward driver.

9) Invest in SmartPhone               

Smart phone is your one-stop shop for the whole lot in rideshare. In reality, exterior to the face-to-face, you acquire with your customers within the car, in each and every other communication he/she is a part of during your drives is associated to your smartphone.

Firstly, make sure that your phone is dependable. It is component of your job to have a contact channel open, so unfortunate equipment can effect in problems that you actually cannot manage to pay for to have occured. 

Rideshare Business Rider Driver

  • 11 months 3 days ago

Important Decisions to Make To Maintain High Standards in Your Business

Jilli Rose
Whether you are a start-up business or a business that has been standing for quite a while, your reputation as a business is critical for the functioning of it. Not just your reputation but the image of your business or brand is also very important; the people or the customers must be able to visualize your business when they think of it andit is your duty as the owner to build this image, a positive and radiant image that will stand out from the rest and remain in their minds long after their encounter with it. So the big question is, how can one go about doing this? At first it may sound daunting and seem like such a big feat, I mean think about it, the responsibility of building a powerful image in the minds of many different types of people sounds scary. But really, if you look at it more prospectively you will learn that this is not quite true and is also easier than it sounds. The key is to pay attention to little things rather than only the bigger picture.


Build a Brand Not a Company

If your sole purpose to maintaining high standards in your business is to build a company then you would not really succeed at building that strong influential image in peoples mind. Instead, focus on creating a brand, something that stands out and is memorable.To do this, it is very important that you hire a proper creative production agency, one that is reputed and caters to each company and helps build a brand that is relevant to each specific company. This is important because you certainly do not want to to look like the rest out there and if your business’s specific positive attributes are not highlighted adequately then essentially the creative company has failed you. So be picky when choosing one and only choose one that comes highly recommended.

 Image Source: Unsplash

TreatYour Customers Well

Never ever forget that it is the customers that keep your company going and not your hard efforts. Your hard efforts ensure that there are customers to keep it running but if those efforts are in vain and no customers turn up, then essentially you have no business. Keeping that inmind, be sure to love your customers and treat them in such a way that they remain happy and loyal to you. Building the trust of your customers can go a very long way, this is so because, if there is one happy customer, they will talk to their friends and family and recommend your company, if those people are in turn happy, they will do the same and so on.


Don’t Skimp On Quality Even If It Costs More

If you try to save a few bucks by reducing the quality of your products then this will in turn come back to you and give you a much greater loss than the amount of money you would have saved. It is very important to remember not to skimp on quality to save a bit of money because the effect can be negative on your whole company. 


  • 11 months 1 week ago