Load Calculation - converting set analysis formula

[#1]

Hi, I would like to do the following calculationg during load. However, I don't think we can do set analysis during load. The calculation is summing up REV (revenue) based on start and expiry date of the contract substracted by the REP (repairs) based on start and expiry date.

Thanks a bunch!

sum( {$<TranDate={'>=$(=(min(GM_START)))<=$(=(max(GM_EXP)))'}>} REV )
- sum( {$<TranDate={'>=$(=(min(GM_START)))<=$(=(max(GM_EXP)))'}>} REP ) as profit

your friendly neighborhood noob,

Chhai.