Compare places with data
Build a comparison using consistent periods, units, populations and definitions.
Prepare the task
Two numbers are not comparable merely because their labels look alike. Keep the definitions and transformations with the result.
- Precise question and territories
- Original files and documentation
- Intended period and unit
Follow the method
- 1Align scope
Check territorial boundaries, period and covered population. Record definition changes before calculating.
- 2Compare units
Separate totals, rates and per-person measures. Retain the formula and a denominator matching the relevant period.
- 3Present limits
Keep missing values, revisions and download dates identifiable. Explain what remains incomparable instead of inventing a value.
Two towns have very different populations: a total and a per-person value answer different questions; explain the choice instead of mixing them.
Choose the resource for the missing evidence
The directory records identify publishers and link to their official services. Choose by task; inclusion does not guarantee an outcome.
| Task | Resource | Check |
|---|---|---|
| Read a French statistical definition | Insee | Compare the series period and territory. |
| Explore a European series | Eurostat | Read codes, units and methodological notes. |
| Find a dataset and producer | data.gouv.fr | Retain documentation and original file. |
Compare these directory resources side by side →
A completed record to understand the method
Fictional example: values, times and situations below demonstrate how to document a decision. They do not describe an actual service or application.
| Element | Observation in the example | Next action |
|---|---|---|
| Area A | 120 events / 10,000 residents | 12 per 1,000 |
| Area B | 180 events / 30,000 residents | 6 per 1,000 |
| Reading | B has more events; A has the higher rate | Also compare period, definition and population |
Keep a useful record
Use these fields in your own notes. This page does not collect your documents or personal details.
- Dataset, producer and version
- Territory, period, unit and population
- Formula and denominator used
- Missing values and comparison limits
Read these points directly on this page.
If definitions or periods cannot be aligned, disclose the difference and limit the comparison.
Common questions
Does a blank cell mean zero?
No. Check whether it represents missing, inapplicable or another coded value.
Can I use the newest population figure?
Check that it matches the measurement’s period and boundaries.
A municipality changed boundaries between years. What next?
Identify the geography used by each table, not just its displayed name. Look for a series recalculated to common boundaries or a documented correspondence table. If comparable areas cannot be reconstructed, present the values separately and explain the break.
A table gives percentages without counts. Can I combine two areas?
Look for each rate’s numerator, denominator and period. Without them you cannot correctly weight the groups to calculate the combined rate. Keep the two percentages separate and state which count is missing.