UA Ledger · Measurement Lab · draft for review

Measure how much an event table changed after the first snapshot

Synthetic teaching inputs. No real campaign results or industry defaults. Change the values to inspect the model. Calculations run locally; this page sends no data and does not retain inputs after closing.

Freeze the event definition, date boundary and filters before taking the first snapshot. Re-run the same query at a later timestamp, keeping both counts and the extraction times. Compute the added count and its share of the later total. When the count falls instead, investigate deletion, deduplication or changed query logic rather than forcing a late-arrival explanation.

Calculated outputs

Assumption sensitivity

Only later varies; all other inputs are held constant. This is not a probability range.

Equations

• Added events: later-early
• Added share of later total %: 100*(later-early)/later
• Change from early snapshot %: 100*(later-early)/early

Additional constraints: true. The field minimums also apply.

Limits

Two snapshots do not prove final completeness. Query changes, duplicate repair and deletions can also move a total; preserve query version and extraction time with any real evidence.

Google Analytics BigQuery Export schema · primary documentation checked 19 September 2026.