12/31/2009 12/31/2008 01/01/2008
Trade accounts receivable 306,123 204,068 162,092
(-) Provision for doubtful accounts (42,171) (37,963) (29,764)
263,952 166,105 132,328


Due dates of the receivables are as follows:

       
12/31/2009 12/31/2008 01/01/2008
Due 160,826 92,968 81,164
               
Overdue:            
Up to 30 days 83,256 59,512 37,911
31 – 60 days 15,288 11,562 11,095
61 – 90 days 12,060 8,347 7,926
91 – 180 days 34,693 31,679 23,996
    306,123 204,068 162,092


The average term for receipt of subscriptions receivable is approximately 30 days. The provision for doubtful accounts is principally comprised of amounts overdue from 90 to 180 days. Overdue amounts of over 180 days are written off.

Provision for doubtful accounts is shown below:

   
   
At January 1st, 2008 (29,764)
Expense for the year (40,310)
Utilized 32,111
At December 31, 2008 (37,963)
Expense for the year (41,053)
Utilized 36,845
At December 31, 2009 (42,171)