I went population-first, broke SF into commuter segments by distance, then tried to back into a dollar figure using average ride frequency and pricing.
Clarify the scope of 'electric scooters' (e.g., shared rental vs. personal ownership) and the definition of 'total addressable market' (annual revenue opportunity). Then use a top-down or bottom-up approach to estimate the number of potential users and average spending, ensuring to state assumptions clearly and sanity-check the final number.
Pro tip: Show adaptability by acknowledging that the estimate is rough and that you would refine it with real data (e.g., population density, scooter adoption rates). Also, mention that for Google, the TAM could include software/services (e.g., maps, ads) beyond just hardware sales.
Ask clarifying questions to define the scope: Are we estimating the market for shared scooters (e.g., Lime, Bird) or personal scooters? Is it annual revenue or number of units? What is the geographic boundary (San Francisco city limits)?
Decide between top-down (start with population and segment) or bottom-up (start with individual usage and scale up). For a city like San Francisco, a bottom-up approach using population segments (residents, commuters, tourists) is often more intuitive.
Segment the population into likely users: residents (adults), commuters, and tourists. Apply adoption rates based on factors like age, income, and alternative transportation availability. For shared scooters, consider frequency of use; for personal, consider ownership rates.
For shared scooters, estimate average rides per user per year and cost per ride. For personal scooters, estimate the average purchase price and replacement cycle. Include ancillary revenue (e.g., subscriptions, ads) if relevant.
Multiply users by spending to get TAM. Sanity-check by comparing to known data (e.g., total scooter trips in SF, population size) and adjust assumptions if the number seems unrealistic.
AI-generated suggestions, not part of the candidate's original notes. May be inaccurate — verify before relying on them.