Finding the decade with largest records, SQL Server

Question

I have the following db diagram :

I want to find the decade (for example 1990 to 2000) that has the most number of movies. Actually it only deals with "

Answer 1

   SELECT floor(Year(getdate())/10)*10
        , floor(year('5/11/2004')/10)*10
        , floor(Year('7/23/1689')/10)*10
        , floor(Year('7/09/1989')/10)*10