
	Inventory

The components of inventory are summarized as follows:



	As of December 31,
(In millions)	2013		2012
Raw materials	$	115.0	$	101.8
Work in process	435.4		244.9
Finished goods	108.6		100.7
Total inventory	$	659.0	$	447.4

In prior years AVONEX PEN units, which have been assembled but not yet packaged, were classified as finished goods. For the year ended December 31, 2013, they are classified as work in process. We reclassified $14.4 million as of December 31, 2012 to be consistent with this new presentation.

The components of inventory by product are summarized as follows:



	As of December 31,
(In millions)	2013		2012
AVONEX	$	176.9	$	144.0
TYSABRI	170.9		114.8
TECFIDERA	33.6		—
Other	162.6		86.8
Total finished goods and work in process	544.0		345.6
Raw materials	115.0		101.8
Total inventory	$	659.0	$	447.4

As of December 31, 2013 and 2012, $93.7 million and $38.3 million, respectively, of our inventory, including costs associated with our ELOCTATE, ALPROLIX and PLEGRIDY programs, have been capitalized in advance of regulatory approval and included in Other in the table above. For information on our pre-approval policy, please read Note 1, Summary of Significant Accounting Policies to these consolidated financial statements

Amounts written down related to excess, obsolete, unmarketable or other inventory are charged to cost of sales, and totaled $47.3 million, $24.8 million, and $25.4 million for the years ended December 31, 2013, 2012, and 2011, respectively.