X Company is considering buying a part next year that they currently make. This year's production costs for 3,500 units were as follows:

		Per-Unit	Total
Direct materials		$3.22	$11,270
Direct labor		3.69	12,915
Variable overhead		3.60	12,600
Fixed overhead		4.10	14,350
Total		$14.61	$51,135

A company has offered to supply this part to X Company for $13.24 per unit. If X Company accepts the offer, it will still incur fixed costs of $7,032, but it will be able to lease the resources that will become available from not making the part for $2,600. Next year's expected production level is 4,000 units. At what production level would X Company be indifferent between making and buying the part next year?