dtype in not working in mad() function

[ift38375]

Ability to use NaN values with columns of integer type is latest pandas feature (and still experimental).
As of Pandas 0.24.x you can do this, e.g.

import pandas as pd
import numpy as np
diSales= { 2016:{'qtr1':34500,'qtr2':56000,'qtr3':47000,'qtr4':49000},
           2017:{'qtr1':44900,'qtr2':46100,'qtr3':57000,'qtr4':59000},
           2018:{'qtr1':54500,'qtr2':51000,'qtr3':57000,'qtr4':58500},
           2019:{'qtr1':61000}
         }
df = pd.DataFrame(diSales, dtype=pd.Int32Dtype())
df.mad(axis=0)

df.info() returns integer dtype, but df.mad still returns float.

Output:
2016    6062.5
2017    6250.0
2018    2500.0
2019       0.0
dtype: float64

Still showing dtyle : float64 in output after using your code which have line: df = pd.DataFrame(diSales, dtype=pd.Int32Dtype()).why ? What is use of this line ?