metric-reconciliation

name	metric-reconciliation
description	Investigate and resolve metric discrepancies across data sources, systems, or time periods. Activate when metrics from different sources don't match, after a data migration, or when a dashboard figure doesn't match a report.

When to use

• Two systems report different revenue, user counts, or other KPIs for the same period
• A dashboard metric doesn't match the figure in an emailed report
• Validating data accuracy after a pipeline or system migration
• Month-end close requires reconciliation between finance and analytics systems
• A stakeholder challenges a reported number and you need to trace the discrepancy

Process

1. Load data from each source — connect to or import all relevant datasets (DB queries, CSVs, API exports)
2. Standardise formats — align date formats, numeric types, null handling, and categorical labels across sources
3. Aggregate at comparison level — roll up to the grain where comparison makes sense (e.g. daily totals, monthly cohort)
4. Join and diff — merge sources on the comparison key; calculate absolute difference, percentage difference, and direction
5. Categorise discrepancies — classify gaps by severity (within tolerance / investigate / critical) using defined thresholds
6. Investigate root causes — analyse patterns: timing lags, filter differences, definition mismatches, currency/unit issues, deduplication logic
7. Drill down — isolate specific dates, transaction IDs, or segments where discrepancies are largest
8. Report findings — document root cause, magnitude, and remediation steps

Inputs the skill needs

• Required: two or more data sources or exports to compare
• Required: the metric(s) to reconcile and how each source defines them
• Required: acceptable variance threshold (e.g. ±0.5%)
• Required: time period and comparison granularity (daily, weekly, monthly)
• Required: the join key that links records across sources (date, transaction ID, customer ID)

Output

• Reconciliation report documenting sources, methodology, discrepancy magnitude, root cause, and remediation
• Discrepancy detail file — row-level diffs for the records that don't match