Examples

import numpy as np
import pandas as pd

df = pd.DataFrame([[3.0, 2.0],
                   [5.0, np.nan],
                   [2.0, 0.0]],
                   columns=list('XY'))
df

	X	Y
0	3.0	2.0
1	5.0	NaN
2	2.0	0.0

By default, iterates over rows and finds the product in each column:

df.cumprod()

	X	Y
0	3.0	2.0
1	15.0	NaN
2	30.0	0.0

To iterate over columns and find the product in each row, use axis=1

df.cumprod(axis=1)

	X	Y
0	3.0	6.0
1	5.0	NaN
2	2.0	0.0