Investment in Available-for-Sale Securities

The following is a summary of the Company’s investment in available-for-sale securities as of December 31, 2011:

	Cost		Unrealized Gains		Unrealized Losses			Fair Value
U.S. federal agency securities	$	15,153	$	411	$	-		$	15,564
Corporate debt securities		1,725,402		11,154		(13,970	)		1,722,586
Certificates of deposit		776,244		1,222		(23,843	)		753,623
	$	2,516,799	$	12,787	$	(37,813	)	$	2,491,773

The following is a summary of the Company’s investment in available-for-sale securities as of December 31, 2010:

	Cost		Unrealized Gains		Unrealized Losses			Fair Value
U.S. federal agency securities	$	273,103	$	1,273	$	(34	)	$	274,342
Corporate debt securities		1,803,892		3,994		(8,343	)		1,799,543
Certificates of deposit		1,927,084		22,438		(7,863	)		1,941,659
	$	4,004,079	$	27,705	$	(16,240	)	$	4,015,544

The Company’s investment portfolio had a net realized loss of $5,919 and $992 for the years ended December 31, 2011 and 2010, respectively. The Company’s investment portfolio has fifteen positions with an unrealized loss as of December 31, 2011.

The cost and fair value of investment in available-for-sale debt securities, by contractual maturity, as of December 31, 2011, are as follows:

	Cost		Fair Value
Due within one year	$	1,693,690	$	1,690,175
Due after one year through three years		709,320		686,033
Due after three years		113,789		115,565
	$	2,516,799	$	2,491,773

Expected maturities will differ from contractual maturities because the issuers of certain debt securities have the right to call or prepay their obligations without any penalties. The Company has classified the entire fair value of its investment in available-for-sale debt securities as current assets in the accompanying balance sheets.