pandas dataframe group year index by decade
if your Data Frame has Headers say : DataFrame ['Population','Salary','vehicle count']
Make your index as Year: DataFrame=DataFrame.set_index('Year')
use below code to resample data in decade of 10 years and also gives you some of all other columns within that dacade 
datafame=dataframe.resample('10AS').sum()
suppose I have a dataframe with index as monthy timestep, I know I can use dataframe.groupby(lambda x:x.year) to group monthly data into yearly and apply other operations. Is there some way I could quick group them, let's say by decade? 
thanks for any hints.