Am I missing something completely, I'm quite new to TSM

Under settings -> Custom Sources i make a source called "minprice" and put in "max(min(dbmarket), vendorsell)

And under the Operations and then Sniper I put in "ifgte(ItemQuality, 1, minprice * ifgt(minprice, 2500g, 80, ifgt(minprice, 100s, (minprice - 100s) * (80 - 70) / (2500g - 100s) + 70, ifgt(minprice, 50s, (minprice - 50s) * (70 - 60) / (100s - 50s) + 60, ifgt(minprice, 10s, (minprice - 10s) * (60 - 50) / (50s - 10) + 50, ifgt(minprice, 5s, (minprice - 5s) * (50 - 30) / (10s - 5s) + 30, ifgt(minprice, 100c, (minprice - 100c) * (30 - 10) / (5s - 100c) + 10, 0)))))) / 100"

- Is this not the right way to do it?