Measure outcome page changes (v2)

Measure how AI-assistant visits to sets of changed pages moved against the rest of the site's AI-assistant visits, before and after each change, in the organization's first chosen source (a Google Analytics property, a Shopify shop, or a Vercel project). Each change names its pages (URLs or paths) and the days the change went live between; the answer compares up to 56 days before with up to 56 days after and reports the relative change with an approximate 90% range, or says why it cannot (not connected, too early, too few visits, nothing to compare with). It measures a provider's visit counts only and changes nothing; it is sent as a write only because each change is an object.