This excerpt taken from the MAC 8-K filed Jul 5, 2005.
Minimum rents from tenants are recognized on the straight-line basis. The excess of accrued straight-line rents over billings, if any, is reflected as deferred rent receivable on the accompanying Consolidated Balance Sheets, net of a reserve for uncollectible amounts of $4,190,594 and $4,133,237, at December 31, 2004 and December 31, 2003, respectively. The established reserve is a function of each individual tenants remaining lease term in conjunction with an internal assessment of their creditworthiness. Based upon provisions of tenant leases, revenues associated with tenant reimbursements are recognized in the period in which the expenses are incurred. Percentage rent is recognized when the tenant reports sales exceeding the annual applicable sales breakpoint.