By Michael Nocito , data analyst · Published August 7, 2026 By the end of this page you can write a month-over-month growth query and trust its answer. You will know the growth formula and how to say it in a sentence, what LAG() actually does, and the three traps that produce wrong percentages without producing an error: integer division, the empty first month, and the missing month. It is about twenty minutes. Here is what to actually do today. Before you trust any growth query you hav...