Each daily run compiles a fixed set of Groovy source files using current
(master) and the latest releases of Groovy 3.x, 4.x and 5.x. The current
measurement from the same run is divided by each series, so current = 1.0 by
construction. Values above 1 mean that version compiles faster than current; values below
1 mean it compiles slower. The trends show how current drifts relative to the released lines.