Cohort Analysis for Startups: Six Summary Reports to Understand Your Customer Base (With Code)

The article presents a practical framework for cohort analysis tailored to startups, emphasizing its role in revealing customer growth patterns, churn dynamics, and the impact of product or marketing initiatives. It outlines six core reports that collectively offer a comprehensive view of customer behavior: average revenue per customer over time, individual account growth trajectories, typical account growth curves, cohort size distributions, average monthly revenue by cohort, and comparative cohort performance across time. These visualizations enable founders to assess how new versus existing customers contribute to revenue, gauge the effectiveness of marketing spend, and identify shifts in customer acquisition quality.

Implementation is demonstrated using R, with the author recommending Hadley Wickham’s `plyr` for data manipulation and `ggplot2` for plotting. The workflow starts from a simple tab‑separated file containing dates, company names, and monthly revenue. The script calculates cohort start dates, aggregates revenue, and produces line and bar charts that illustrate both individual and aggregate trends. The methodology relies on standard statistical operations—means, sums, and month‑level grouping—and can be adapted to other metrics beyond revenue.

The piece is aimed at early‑stage companies operating in the U.S. market, with a focus on monthly recurring revenue as the primary metric. By providing ready‑to‑run code and clear visual templates, it equips founders with actionable insights into customer lifetime value and cohort health without requiring advanced database skills.