Loop through group of values, calculate a total

[JHizzal]

The Issue:
I have a fairly large excel file (2000+ rows) that contains groups of values in column A (that vary in length), then numerical values in columns C and D that are associate with those values. I need to go through each of these groups and calculate a total based on adding all the values for that group that are located in columns C and D.

The one nice thing is that the values of the groups are all together.

The Problem:
My problem is that I'm having a tough time trying to figure an algorithm to compute the proper total. In Java I could use maps and lists and associate it through creating dynamic classes. VBA is a bit different.

Any help would be greatly appreciated.

Attached is a sample workbook. Sheet 1 contains the data. Sheet 2 is where I'm trying to print the summary data and what I'm wishing the data to look like.