There are few ways to do this. However for ease you might try creating two Running Totals. One for each of the values you want counted. I would select the field holding the two values and then under evaluate use the formula then put 'OC' and save it as rtOC then do the same for 'TFC' and call it rtTFC. Then place these fields where you want them on the report. In theory this should do what you want.
Regards,
John W.
www.CustomReportWriters.net