Date(Index) Date_Year_Key   Date_Month_Key  Is_Late

2014-01-01  2014        1       1
2014-01-03  2014        1       1
2014-01-03  2014        1       1
2014-01-03  2014        1       1

temp=big_cust_tm_series.groupby(['Date_Year_Key', 'Date_Month_Key'])['Is_Late'].mean()
temp.plot(figsize=(15,5),
          title= 'Late records(Monthwise)', fontsize=14)

import statsmodels.api as sm
sm.tsa.seasonal_decompose(temp).plot()
result = sm.tsa.stattools.adfuller(temp)
plt.show()

AttributeError: 'MultiIndex' object has no attribute 'inferred_freq'