C-Spec pace at every track

Every event the class ran, at any track, oldest to newest on the chart and newest first in the table. Each point is the class's best lap as a share of the field's best on the same day (every class that ran that day but the ones shown, each scaled by its usual pace against SM and averaged, with each shown class's own track character taken out, so one figure reads the same across years and tracks): the weather and the day cancel out, so one figure compares across years where lap times cannot, and across tracks too, since the class's own character at each track is taken out. A track with only one or two events on record is corrected less, since there is less to go on. A best from fewer than three cars is greyed. The rule changes that took effect between two events are folded between their rows.