Simpson's Paradox in Measuring Net Dollar Retention Rate
FEBRUARY 2, 2020
Net Dollar Retention is one of the most important metrics is a SaaS business. It measures the value of a cohort of customers over time including expansion, cross-sell, and churn (loss of revenue). But how do you measure NDR? Imagine this is your company’s data. The first column is the cohort month for each cohort in a year. The second column is the revenue of this cohort in their first month. The second colum is a random number between -20 and +20 that is the NDR for that cohort.