Very slow aggregation performance on object type column with Decimal datatype values
#### Problem description
I have a dataframe with a million row and 10 columns. I want to groupby on 3 columns and sum on 1 column. If the column to be aggregated is float it takes less than a second to get the result. But if the column is a object with Decimal datatype values it take 70 seconds to return the result. I know it is not a numpy datatype column and it would take longer but is 70 seconds for aggregating million rows seems reasonable. Is there any way to get results faster with Decimal

