VALERO ENERGY CORP/TX | 2013 | FY | 3

6.
RECEIVABLES
Receivables consisted of the following (in millions):
 
December 31,
 
2013
 
2012
Accounts receivable
$
8,650

 
$
8,061

Commodity derivative and foreign currency
contract receivables
98

 
136

Notes receivable and other
49

 
26

 
8,797

 
8,223

Allowance for doubtful accounts
(46
)
 
(56
)
Receivables, net
$
8,751

 
$
8,167


Changes in the allowance for doubtful accounts consisted of the following (in millions):
 
Year Ended December 31,
 
2013
 
2012
 
2011
Balance as of beginning of year
$
56

 
$
48

 
$
42

Increase in allowance charged to expense
13

 
21

 
21

Accounts charged against the allowance,
net of recoveries
(23
)
 
(13
)
 
(14
)
Foreign currency translation
—

 
—

 
(1
)
Balance as of end of year
$
46

 
$
56

 
$
48

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