Federer, who lifted his 99th ATP title in Basel, won 5,097 individual points during 2018.
Many of those came in the Australian Open, which he won after beating Marin Cilic, while Federer also took the Rotterdam Open and Stuttgart Open.
That helped him earn $7.6million – at a breakdown of exactly $1491 a point.
Novak Djokovic ended as the year-end No.1 and he topped the efficiency stakes with $2176 per winning point.
The Serb, who lost in the ATP Finals to Alexander Zverev, ended the year taking home $12,609,672.
Rafael Nadal was second at $2024 per winning point while Alexander Zverev earned $1288 every time he won one.
In terms of the highest percentage of matches won, Nadal came out on top.
The Spaniard had the best match-record winning percentage of players in 2018 at 91.8 per cent (45-4).