Lizana Clinic uses client-visits as its measure of activity. During December, the clinic budgeted for 4,400 client-visits, but its actual level of activity was 4,380 client-visits. The clinic has provided the following data concerning the formulas used in its budgeting and its actual results for December Data used in budgeting Fixed elementelemen Variable per month client visit $36.40 Revenue Personnel expenses Medical supplies Occupancy expenses Administrative expenses Total expenses $28,400 1,300 10,300 7400 $47,400 $12.40 6.40 1.00 0.50 $20.30 Actual results for December: Revenue $127,830 Personnel expenses Medical supplies Occupancy expenses Administrative expenses $70,140 $21,116 $14,210 $7,890 The activity variance for netperating Income In December would be closest to