SELECT  year
             , month
             , south
             , west
             , midwest
             , northeast
             , south + midwest + west + northeast AS total
            , south / total * 100 as south_per
            , west/total * 100 as west_per
            , midwest/ total * 100 as mid_per
            ,northeast / total * 100 as NE_per
FROM tutorial.us_housing_units
where year >= 2000