Each game is weighted equally regardless of the day it was played.
Games are weighted based on the day they were played. The value of games on each day are given by a line through the origin and a slope you provide. Games on the last day are equal to the slope while games on any other day are the slope multiplied by the percent of days in the season that have passed.
The season is divided into equal sized intervals, according to the days in the season, with a game in each interval weighted the same. The weights used in each interval are provided by you.