The appropriate response is a weighted average. It is a mean ascertained by giving qualities in an informational index more impact as indicated by some characteristic of the information. It is normal in which every amount to have arrived at the midpoint of is allocated a weight, and these weightings decide the relative significance of every amount on the normal.
The number of runs score per game in the last season is 14/18=0.78, in this season is 12/15=0.8 0.78<0.8, so this season the player scored more runs per game