Summing up numbers, based on certain criteria.

[AnthonyWB]

Hello everyone. I have the following problem to solve. I have two columns in an Excel worksheet. Column H = Security ID, and a Column L = MTM. Security ID is an ID for trades, with MTM representing their (its) respective market-to-market value. Now here is the kicker, the Security ID is NOT unique and I would like to sum up the MTM values for each instance of that Security ID, and then determine if that sum is less than 10,000, in which case I would want to place the word "Terminated", into Column Y within the respective cells corresponding to that specific Security ID. Please see the example below,

Column H = Security ID
0332JPYSTR58
0332JPYSTR58
0332JPYSTR58

Column L = MTM
-12,304,706.94
12,306,942.01
0

Column Y = Terminated
Terminated
Terminated
Terminated


Note that -12,304,706.94 + 12,306,942.01 + 0 = 2,235 which is less than 10,000, consequently the word "Terminated" has been placed into column Y corresponding to each instance of the Security ID, in this example 0332JPYSTR58.

I am uncertain where to begin coding. A For Each statement I am certain, but thats about it. Any help would be greatly appreciated.