How many laptops are sold in US every year? Any thoughts?

# How many laptops are sold in US every year?

Using the replacement-framework:

**Goal: #laptops sold / year**

- #laptops = (laptop/person) * (total amount of people)
- = 0.5 laptops per person (tables and desktop are solid substitutes) * 300M people
- = 150M laptops in total

- Life-span of laptops are approximately 3 years
- #laptops / lifespan
- = 150M/3y = 50M/y

- This could be the answer or if you want to integrate a trend, do the following:
- negative trend because of more substitutes (tables, mobile phones, etc.)
- Approximately 5% per year, so 5% of the total amount will not be replaced
- = 150M*5% = 7.5M
- Answer of 50M - 7.5M = 42.5M

**The answer would be: In average 42.5M laptops will be sold per year in the US**.

(edited)

I highly recommend the book "Case in Point" by Marc P. Cosentino for this type of question:

Quote: "

- Make assumptions and break the population down by generation.
- Determine the number of cell phones in each generation.
- Calculate the number or percentage of laptops out of each generation's number of laptops.
- You may want to draw a chart to show how well organized you are and how logically you think. It also makes it easier for the interviewer to follow your thought process.

Assumptions: 320M Americans, life expectancy of 80 yrs, even distribution among the ages. I'm going to divide it into generations 0-20, 20-40, 40-60, 60-80. That means 80M people per generation." [read more on p. 17/18]

Kids 0-16 or 64M American children don't own computers. Out of the remaining 4M kids I'll assume that 3M have a laptop...

Reason through your numbers for each generation and fill in the chart as you go along.

I would come up with a 150M laptops in the US. However, the question called for the number of laptops sold each year. The average laptop lasts for 3 yrs (assumption). I'll assume that 80 percent will upgrade to a newer model. That means 50M x 0.8 = 40M. Thus 40M laptops where sold last year...

There are quite a few ways to crack the problem. However, my favorite approach is by segmenting the population.

So you start with total population in the US (i.e. 320 million) and the life expectancy (i.e. 80 years).

Then categorized population into segments (e.g. children, college student, working level, retirement). You can simply the maths by assume that population is uniformly distributed then assign the age range to each segment,and you will be able to calculate how many people are there in each segment.

Next is to assign percentage of those who own laptop in each segment.

Now here is the important part. You will have to estimate the life time of laptop, for example 5 years. This will mean that laptop will have to be replaced every 5 years.

So you cannot just assume that number of laptop sold will be equal to number of laptop owned. It need to be divided by years of replacement to get to final answer.

Hope it help!

## Related BootCamp article(s)

## Interviewer-Led vs Candidate-Led cases

Case Interviews can be led by the candidate or by the interviewer: In Candidate-led cases the main challenge is the structure. In Interviewer-led cases the main challenge is to adapt quickly

0 Comment(s)## Market Sizing

Market Sizing Cases are used to test your quantitative and reasoning skills. The interviewer evaluates your structure, numbers-handling and business sense.

15 Comment(s)## Important Facts

It's essential to know some key figures regarding geographies, population, economies for your case interviews. We summarized them for you here.

9 Comment(s)## Related case(s)

Your client, large automotive OEM WyCar, has developed its first fully electric vehicle (EV) and introduced it as a pilot on the Austrian market last year. However, sales have been far below the expected numbers. The management has engaged you to support them in understanding the reasons and advise ... Open whole case

You have inherited the “Old Winery” from your grandfather, a winery which has been family owned for five generations and can be dated back to the 16th century. Half of the eleven hectares are used to grow white grapes, the other half to grow red grapes. They are grown in the conventional way, i.e ... Open whole case

Nutripremium is a very well-known premium nutrition food company in Europe (€1 billion revenue last year). It is based in Spain and has an excellent market share not only in its home country but also in Portugal, France, Italy and Germany. Nutripremium has two main lines of products: Vitam ... Open whole case

Beyer, one of the biggest pharmaceutical companies in the world, just invented a very reliable vaccine against Chickenpox, a disease that affects children in the age from 2 to 16 years. Beyer came to you wondering what their potential sales in Europe in the first year would be if they launched th ... Open whole case

How many gas stations are there in Paris? Suppose a friend of yours wants to open a gas station in Paris. What aspects should he consider? Open whole case