Methodology
- 1
Collect
Each source is pulled on its own schedule: daily for station feeds, weekly for the bulletin, monthly for Norway and Switzerland. Raw pulls are staged, never published directly.
- 2
Validate
A staged pull must pass count, sample and geography checks against the previous snapshot. A pull that fails any check is discarded and the previous snapshot stays live.
- 3
Publish
Validated data flips atomically to the published snapshot. Every figure on the site reads the published snapshot, so a page never mixes two editions.
- 4
Aggregate
Averages, cheapest figures and rankings are precomputed from the published snapshot. A cheapest figure needs a price no older than 30 days; averages use every accepted price.
- 5
Check
After each publish, sampled stations are compared field by field with the source feed. The checks on this page describe exactly what ran.
Averages and cheapest figures
An average is the mean of every accepted price for a fuel in an area. A cheapest figure is the lowest fresh price, and is always labelled "from" at city and region level. The two statistics answer different questions and are never blended: a cheapest price is never presented as an average.
Tax zones
Some territories run a different fuel tax regime: the Canary Islands, Ceuta and Melilla for Spain, and the French overseas departements. Their stations are labelled, ranked inside their zone, and never enter mainland averages or cheapest lists, because mixing tax regimes would flatter or punish the wrong stations.
Corrections
Source data is republished as received. If a source corrects a price, the next publish carries the correction with its new date; Euro Litre does not silently rewrite published history. If you spot an error, the station page shows the exact source and date to check against.