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Calculation Airport Passengers in 1 year


Hi everyone,
I was recently asked to calculate the passengers of an airport in 1 year. I used the method of what I assume would be the bottom-up approach: # of runways, utilization of runways, opening hours airport, # of planes on runway, capacity planes and utilization of planes, etc. I got pretty close to the exact number, so I assume this was a good approach :)
However, could someone please explain to me how the top-down approach would look like? Would I start with the percentage of travellers flying for leisure/work etc.? And how would I proceed then?
Thanks a lot in advance!


replied on 05/18/2017
Ex-Bain consultant who cracked interviews at McK, BCG, Bain

Hi Franziska,

I'd try the following:

1. The population served by a particular airport (if there are several airports in an area, also assume an airport's share)

2. Based on personal experience, estimate the number of people flying for business and leisure (tough)

3. Estimate how many times a year they fly (easier)

As always with these cases, there are many ways to do it and this is just one. Also this top-down approach will be less accurate than what you came up with.

Hope it was helpful!



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