Serie A

Every match is scored against a pre-game probability, and the model's log loss is compared with the same trailing window carrying no ratings at all. The figure is that improvement: how much knowing the clubs beats knowing nothing. Serie A runs from 1929-30 to 2024-25, 28,822 matches.

Surplus is comparable within a league and only loosely across leagues, because league size and era differ.The baseline is each league's own era, so a high figure means a predictable league, not a strong one.

Historical results compiled by James Curley, github.com/jalapic/engsoccerdata

Squad values are read at the end of each season (June) and summed across every club in that season's league whose squad is priced. The n beside a figure is the players valued behind it; a club under fifteen priced players carries no value at all rather than a low one, so it is left out of both the top and the total.

The series starts at 2012-13 because that is where the value data starts. Earlier totals are an artefact of which players had been priced at the time, not a cheaper era, so nothing here reaches back past it.

Player valuations from Transfermarkt via github.com/dcaribou/transfermarkt-datasets (CC0)