Cardillo Inc., an escrow agent, has provided the following data concerning its office expenses:

	Escrows Completed	Office Expenses
January	99	$13,181
February	111	$13,598
March	129	$14,239
April	133	$14,357
May	152	$15,095
June	104	$13,335
July	118	$13,847
August	100	$13,211
September	103	$13,283

Management believes that office expense is a mixed cost that depends on the number of escrows completed. Note: Real estate purchases usually involve the services of an escrow agent that holds funds and prepares documents to complete the transaction. Using the high-low method, the estimate of the fixed component of office expense per month is closest to: