SORTED.group by and count average of two columns [ sum of col 1 / sum of col 2 ]

[BSDevo]

Solved.

filtered_df["RPM"] = filtered_df["Rate"]/filtered_df["Miles"].groupby(filtered_df["PuState"]).transform('mean')

Turns out i solved it by removing ()

EDIT: No , it makes incorrect calculations

EDIT#2 - sorted.

filtered_df["StateRate"] = filtered_df["Rate"].groupby(filtered_df["PuState"]).transform('mean')
filtered_df["StateRPM"] = filtered_df["StateRate"]/filtered_df["Miles"].groupby(filtered_df["PuState"]).transform('mean')