Balance Sheets (USD $)	Mar. 31, 2013	Mar. 31, 2012
ASSETS
Cash and cash equivalents	$ 2,509,683	$ 1,544,536
Marketable securities, short term	9,711,029	17,551,629
Accounts receivable, net of allowance for uncollectible accounts of $15,000	2,521,395	2,684,840
Inventories	3,336,592	3,229,376
Prepaid expenses and other assets	958,147	1,159,852
Total current assets	19,036,846	26,170,233
Fixed assets
Machinery and equipment	8,417,061	7,488,211
Leasehold improvements	1,499,454	720,882
Gross fixed assets	9,916,515	8,209,093
Less accumulated depreciation	6,228,122	5,697,861
Net fixed assets	3,688,393	2,511,232
Marketable securities, long term	73,040,257	54,445,298
Total assets	95,765,496	83,126,763
LIABILITIES AND SHAREHOLDERS' EQUITY
Accounts payable	422,092	663,702
Accrued payroll and other	918,060	867,331
Deferred taxes	440,736	136,872
Total current liabilities	1,780,888	1,667,905
Shareholders' equity
Common stock, $0.01 par value, 6,000,000 shares authorized; 4,862,436 issued and outstanding as of March 31, 2013 and 4,824,745 issued and outstanding as of March 31, 2012	48,624	48,247
Additional paid-in capital	21,200,742	20,974,477
Accumulated other comprehensive income	1,557,726	1,087,456
Retained earnings	71,177,516	59,348,678
Total shareholders' equity	93,984,608	81,458,858
Total liabilities and shareholders' equity	$ 95,765,496	$ 83,126,763