Survey period comparison screen
Count shared collection years and flag incompatible lengths before comparing survey products.
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Use four inclusive calendar years between 1900 and 2100. Enter one year twice for a one-year product.
The starting values are hypothetical. Results update as you edit. Use aggregate or synthetic inputs only.
Calculation results
- Shared collection years
- 1
- Lengths in years
- 5 and 5
- Decision
- Overlapping periods
How to interpret the output
Screens dates only. Even non-overlapping, equal-length periods require compatible geography, universe, questionnaire and price base. Shared years do not establish a specific covariance. Source checked 7 November 2026.
Method reference