I have a cub that looks like this:

year - month | prior year carry over total | hours | [prior year carry over
total + hours]

2004 - Total 300 | 14 | 314
Jan 100 | 4 | 104
Feb 100 | 3 | 103
Mar 100 | 7 | 107

but I need it to look like this:

2004 - Total 100| 14 | 114
Jan 100 | 4 | 104
Feb 100 | 3 | 103
Mar 100 | 7 | 107

The [prior year carry over total] should only be counted once per year and
not summed like it is doing now. How can this be accomplished?

Thanks