Grohs Kennel uses tenant-days as its measure of activity; an animal housed in the kennel for one day is counted as one tenant-day. During December, the kennel budgeted for 2,500 tenant-days, but its actual level of activity was 2,530 tenant-days. The kennel has provided the following data concerning the formulas to be used in its budgeting:

	Fixed element per month	Variable element per tenant-day
Revenue	$ 0	$ 33.00
Wages and salaries	$ 3,800	$ 7.90
Food and supplies	1,000	11.60
Facility expenses	8,600	2.20
Administrative expenses	6,200	0.20
Total expenses	$ 19,600	$ 21.90

The net operating income in the planning budget for December would be closest to: