From Monarch v9 or above, you could use the NOT trap to exclude the lines with OFF at the template/trapping stage. In v6, you don't have that option, but as OddJob suggests, just trap all the lines - you can use the Ã AND Ñ characterS to trap on character and numeric wildcards - and then make filter in your table.
I can't recall whether v6 projects would let you define a single export that bursts the table out for all filters - my guess is that this came later (v8?) and so you'll need to define multiple project exports. Or upgrade