Lose leave balance if not taken

I have a blank of memory and I wild appreciate if someone could help me restoring it :-)

I have a STAT Holiday accrual where if the employee does not use them all, then at Year-End Rollover time, we want to NOT carry over any untaken balance however we want to create a LOST DBA to keep track of STAT hours not taken and not carried over.

I know for instance that in the Rollover Table (e.g. 00005), if I want to limit rolling over to the next year 80 hours, all I need is to write 80 in the amount/rate field of the table, but what if I leave that field *blank? will the system take the zero value as the limit to roll over and therefore that would accomplish what I want?