df["balance"].mul(36902.7).div(100e6)
See [0] for explanations
[0] https://stackoverflow.com/a/52674448
%time df['balance'].apply(lambda x: x * 36902.7 / 100e6).describe() Wall time: 12.6 s %time df["balance"].mul(36902.7).div(100e6).describe() Wall time: 2.33 s
df["balance"].mul(36902.7).div(100e6)
See [0] for explanations
[0] https://stackoverflow.com/a/52674448