What do the colors mean? Looks like the darker green means faster than previous and yellow means slower than previous? Personally I would just make everything yellow except current and put minus values in the last column in red with white bold text so it's clear which ones are slower than previous since those are really the only ones that matter.
It's a heat map showing the fastest result for the releases. The final delta column's heat is vertical to show the worst performance drop. Yeah, maybe I'll make the delta column red to white so it's less confusing.
The final column would be more useful if it were a vertical bar graph with deviation bars above the 0 line for +% and below the 0 line for -%. With MAME short name for the game_x labels A bit like this.... https://gurudumps.otenko.com/temp/deviationgraph.jpg
This graph can be made with about 3 clicks using excel etc.