Compare Rows, Delete duplicate values, Sum values but Retain blank rows

Excel 2003
Raw data is given from Column A to D (Table 1). There is a need to process these raw data so that the processed data is displayed from Colum G to J (Table 2).
The processing logic is as such: For rows that have the same "Time", "Price" AND "Type" columns, adds the "Volume" values and display all information at the first row. Do NOT delete any rows.

RAW Data (Table 1) PROCESSED Data (Table 2)
A B C D G H I J
Time Price Volume Type Time Price Volume Type
8:58:19 2.77 2,000 Buy Up 8:58:19 2.77 4,000 Buy Up
8:58:19 2.77 2,000 Buy Up
9:00:00 2.76 10,000 Sell Down 9:00:00 2.76 10,000 Sell Down
9:00:02 2.76 5,000 Sell Down 9:00:02 2.76 15,000 Sell Down
9:00:02 2.76 5,000 Sell Down
9:00:02 2.76 5,000 Sell Down
9:01:11 2.75 7,800 Sell Down 9:01:11 2.75 7,800 Sell Down