Market Sizing/Estimation: How many K-12 public schools are in the US? How would you estimate this?

Case Interview estimation Market sizing
New answer on Jan 04, 2020
4 Answers
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Anonymous A asked on Dec 31, 2019

Have gone through a solution but I'm way off.

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Luca
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replied on Jan 04, 2020
BCG |NASA | SDA Bocconi & Cattolica partner | GMAT expert 780/800 score | 200+ students coached

It seems to be a standard market sizing that you can tackle starting from total american population, as suggested by others.

If you want to impress you interviewer, once that you have done your estimation, propose to do a sanity check of the result following a bottom up approach. One way could be to list the K-12 schools of your town, calculate the ratio schools/population and apply this ratio to the national population.

Hope it helps,
Luca

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Udayan
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replied on Jan 04, 2020
Top rated Case & PEI coach/Multiple real offers/McKinsey EM in New York /6 years McKinsey recruiting experience

Hi,

Using the standard approach of US population at 320M, avg life expectancy of 80 and equal population distribution you get 4M*12 or approximately 50M children of school age in the US which is more or less what the internet says as well.

Where this gets confusing is total school size - elementary school sizes are much smaller as the costs to run them are lower and there is decent teacher availability (~250 per school), secondary schools are much bigger in size given the higher costs and bunch of other factors such as teachers, school zoning etc (~1,000 per school). If you take a rough average of 500 students per school you end up at ~100,000 schools which is close enough to 132,000 as per the census

Hope this helps,

Udayan

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Antonello
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replied on Jan 03, 2020
McKinsey | NASA | top 10 FT MBA professor for consulting interviews | 6+ years of coaching

Hi,
I would estimate:

  • N. of boys, starting from US population and assuming a constant population for each age group
  • % of boys enrolled in K-12 schools
  • % of public K-12 schools
  • average boys per class and average classes in a school

Hope it helps,
Antonello

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Clara
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replied on Jan 03, 2020
McKinsey | Awarded professor at Master in Management @ IE | MBA at MIT |+180 students coached | Integrated FIT Guide aut

Hello!

In order to help you better: is this part of a case -where you are given a bit more guidance- or is this a brain teaser?

Cheers!

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Luca gave the best answer

Luca

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BCG |NASA | SDA Bocconi & Cattolica partner | GMAT expert 780/800 score | 200+ students coached
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