Automatically remove contents of a cell

Please see the attached spreadsheet. If you take a look at column H, its formula is =SUMIF($A$6:$A$50,A6,$D$6:$D$50). This may not be the best way to do what I am trying to accomplish. The requirement for column H is to compare cells in column A and if they are the same (i.e. "BT"), then I need to sum the values in column D for the cells in where column A are the same. Now the formula above does this however, I only need it to appear in the last cell of the calculation. So for the BT example... it would only add D6&D7 so I would need the "474" result to appear in H7 only. Obviously I would then need this to happen for the remainder of column H. Can this even be done?

Thanks!CWCountTemplate.xls

change your formula to
=IF(COUNTIF($A$6:$A$50,A6)=COUNTIF($A$6:$A6,A6),SUMIF($A$6:$A$50,A6,$D$6:$D$50),"")

Thank You!! That did it!