@Djazz98 Not directly in the available files, its a background translation from wear to expected laptime but it shows the grip amount you will have at a given wear% and yes its especially early on not linear at all ๐ For those who want to do the maths on average one can calculate per percentage of tyre grip 0.3s laptime gain/loss in the game but that works on the total amount of grip a tyre provides not on the grip loss/wear%..
For example:
C5 at 100% has 98% total grip = ~1.20.00s laptime
C5 at 25% only has 93.18% of its grip which means 93.18% of 98% = 91.32% grip which means a loss of ~2s laptime = ~1.22.00s
However C2 at 100% only have 93.5% total grip = ~1.21.35s
C2 at 25% has 94.37% grip left so 94.37% of 93.5% = 88.23% grip which means a loss of ~1.58s = ~1.22.93s laptime
Grip loss at higher wear% is much more promoted at softer tyres though as was shown by a nice graph from David previously
So its in the files as we can see the wear rate, the base grip and the grip loss at certain wear but it requires a lot of simple math to do it for all the tyres and wear haha hope i could somewhat help