Worked cases 1 to 4

Each case below uses the five-step estimate in the same order: Clarify, Structure, Assume, Calculate, Check. Every number is a round approximation chosen for easy arithmetic. Products named here are fictional.

Read each prompt, cover the answer, and spend ten minutes on it yourself before reading on.

#Case 1: The US dog-walking market

Type: market sizing (revenue).

Interviewer We're thinking about a dog-walking app. How big is the annual US market?

1. Clarify

You Two checks. By market, do you mean total consumer spending on paid dog walks in the US, whether or not it goes through an app? And just walking, not boarding, sitting or daycare?

Interviewer Yes to both. Then tell me what an app could earn from it.

2. Structure

You I'll go top-down from households, because dog ownership is a household decision. I'll split dog owners into two segments that behave very differently: regulars who pay for walks every week, and occasional users who book a few times a year. Market equals walks per year in each segment times price per walk.