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Schedule II - Valuation and Qualifying Accounts
12 Months Ended
Dec. 31, 2011
Schedule II - Valuation and Qualifying Accounts  
Schedule II - Valuation and Qualifying Accounts

Years ended December 31, 2011, 2010, and 2009

 

Accounts receivable, allowance for doubtful accounts:

 

 

2011

 

2010

 

2009

 

Balance at beginning of year

 

$

342,682

 

$

473,912

 

$

387,037

 

Provision (Recoveries) credited to expense

 

55,209

 

8,466

 

155,069

 

(Write-offs) and recoveries

 

(19,032

)

(139,696

)

(68,194

)

Balance at end of year

 

$

378,859

 

$

342,682

 

$

473,912