6. Receivables

	December 31,
($ in millions)	2015			2014

Trade accounts receivable	$	759.3		$	800.0
Less allowances for doubtful accounts	(5.4		)	(7.0		)

Net trade accounts receivable	753.9			793.0
Other receivables	131.5			164.1

	$	885.4		$	957.1

Net accounts receivable under long-term contracts, due primarily from agencies of the U.S. government and their prime contractors, were $196.2 million and $205.8 million for the years ended December 31, 2015 and 2014, respectively, and included $144.7 million and $133.3 million at each period end, respectively, representing the recognized sales value of performance that was not yet billable to customers. The average length of the long-term contracts is approximately 2.5 years, and the average length remaining on those contracts at December 31, 2015, was 11 months. At December 31, 2015, $195.1 million of net accounts receivables is expected to be collected within the next year and is related to customary fees and cost withholdings that will be paid upon milestone or contract completions, as well as final overhead rate settlements.

Other receivables include income and sales tax receivables, certain vendor rebate receivables and other miscellaneous receivables.

The company has entered into several regional uncommitted and committed accounts receivable factoring programs with various financial institutions for certain receivables of the company. The programs are accounted for as true sales of the receivables, without recourse to Ball, and had combined limits of approximately $600 million at December 31, 2015. A total of $478.7 million and $197.6 million were sold under these programs as of December 31, 2015 and 2014, respectively.