Inverness Steel Corporation is a producer of flat-rolled carbon, stainless and electrical steels, and tubular products. The companys income statement for the 2013 fiscal year reported the following information ($ in millions):

sales 7400

COGS 6400

The companys balance sheets for 2013 and 2012 included the following information ($ in millions):

2013

current assets

accounts rec net 728

inventories 955

2012

current assets

accounts rec net 628

inventories 866

The statement of cash flows reported bad debt expense for 2013 of $5 million. The summary of significant accounting policies included the following notes ($ in millions):

Accounts Receivable (in part)

The allowance for uncollectible accounts was $7 and $4 at December 31, 2013 and 2012, respectively. All sales are on credit.

Inventories

Inventories are valued at the lower of cost or market. The cost of the majority of inventories is measured using the last in, first out (LIFO) method. Other inventories are measured principally at average cost and consist mostly of foreign inventories and certain raw materials. If the entire inventory had been valued on an average cost basis, inventory would have been higher by $600 and $450 at the end of 2013 and 2012, respectively.

During 2013, 2012, and 2011, liquidation of LIFO layers generated income of $8, $4, and $22, respectively.

Determine the amount of accounts receivable Inverness wrote off during 2013