This excerpt taken from the PGI 10-Q filed May 8, 2009.
Accounts Receivable and Allowance for Doubtful Accounts
Included in accounts receivable at March 31, 2009 and December 31, 2008 was earned but unbilled revenue of $11.1 million and $5.9 million, respectively, which results from non-calendar month billing cycles and the one-month lag time in billing related to certain of our services. Earned but unbilled revenue is billed within 30 days. Provision (recovery) for doubtful accounts was $0.1 million and $(0.4) million for the three months ended March 31, 2009 and 2008, respectively. Write-offs against the allowance for doubtful accounts were $0.4 million and $0.1 million in the three months ended March 31, 2009 and 2008, respectively. Our allowance for doubtful accounts represents reserves for receivables that reduce accounts receivable to amounts expected to be collected. Management uses significant judgment in estimating uncollectible amounts. In estimating uncollectible amounts, management considers factors such as historical and anticipated customer payment performance and industry-specific economic conditions. Using these factors, management assigns reserves for uncollectible amounts by accounts receivable aging categories to specific customer accounts.