((ROUND(({enddate}-{startdate})/30.41))/12) works, {total}+((ROUND(({enddate}-{startdate})/30.41))/12) works, {total}-((ROUND(({enddate}-{startdate})/30.41))/12) works, {total}*((ROUND(({enddate}-{startdate})/30.41))/12) works, but {total}/((ROUND(({enddate}-{startdate})/30.41))/12) breaks it. I didnt know if there is some other way to put it in the formula when every other combo works.