Methodology

Every number on this site comes from prices Fareband observed itself and stored, with the date of observation. This page explains how that works. It is linked from every data component on the site.

How prices are collected

Once a day, Fareband queries fares for each route it tracks and stores every result as an observation, together with the departure and return dates, the trip type, the carrier, the currency and the moment it was read. Prices are stored as whole units of the smallest denomination of their currency — pence, cents, yen — so no rounding error can accumulate. Nothing is averaged before storage, and no observation is edited after the fact.

A price is a fare that was available at the moment it was read. It is not a prediction, not a guarantee, and not an offer. Fares change constantly, and the figure you see when you follow a link may differ from the one recorded here.

What a percentile means here

For each route Fareband computes a band over a rolling window — usually 90 days — from all observations of that route in that window. The 10th percentile is the price that 10% of observations fell at or below. The median is the middle observation. The 90th percentile is the price only 10% of observations exceeded.

The band describes what this route has actually cost recently. It says nothing about what any individual traveller paid, and it does not adjust for cabin class, baggage or how far ahead the booking was made. Observations in different currencies are never mixed inside one band.

When a page publishes

A route page becomes indexable only once it has at least 60 observations, at least 90 days of history and fares from at least 3 distinct carriers. Below any of those thresholds the page stays out of search results and keeps collecting. A page that cannot show an observed figure with its date does not publish at all.

Update frequency

Observations are collected daily. Bands are recomputed nightly for the 30, 90 and 365-day windows. The date shown beneath a price band is the date of the observation it describes, not the date the page was last rebuilt.

Corrections

When a figure turns out to be wrong, the page is corrected and the correction is noted with its date rather than quietly overwritten.