Pandas Persentaile Kumulatif
df['cum_sum'] = df["val1"].cumsum()
df['cum_perc'] = round(100*df.cum_sum/df["val1"].sum(),2)
Cheerful Chipmunk
df['cum_sum'] = df["val1"].cumsum()
df['cum_perc'] = round(100*df.cum_sum/df["val1"].sum(),2)