Estimate one year of worldwide Google Pixel phone unit sales

Estimate how many Pixel phones Google sold worldwide over the last 12 months. Talk through how you build the estimate, state each assumption as you make it, and land on a single number. ```hint Where can people buy one A Pixel is not sold everywhere, and its share of phone sales varies a lot from country to country. Decide which markets belong in the estimate before you put numbers on anything. ``` ### Clarifying Questions - Should I count phones sold to end customers, or units Google shipped to carriers and retailers? - Do all current Pixel models count, including the lower-priced A-series and the foldable, and are refurbished or second-hand phones excluded? - May I use rough outside knowledge, such as total smartphone sales or Android's share in different countries? ### What a Strong Answer Covers - A clear equation that segments the market in a way that matters for Pixel, such as by country group - Labeled, round-number assumptions for smartphone adoption, how often people replace phones, Android's share and Pixel's share of Android - Arithmetic carried correctly to one estimate, with a plausible range - At least one independent sanity check built from a different starting point - The assumptions that drive the answer most, and how real data would refine them ### Follow-up Questions - Which assumption moves your estimate the most, and what data would you use to pin it down? - How would you turn your unit estimate into an estimate of Pixel revenue for the same period? - Google launches Pixel in a new large country. How would you size what that country adds in its first year?