Balance Sheets - USD ($)	Mar. 31, 2016	Mar. 31, 2015
Current assets
Cash and cash equivalents	$ 7,534,593	$ 9,437,262
Marketable securities, short-term	19,697,384	20,099,288
Accounts receivable, net of allowance for uncollectible accounts of $15,000	2,244,086	2,963,974
Inventories	$ 3,205,233	3,742,492
Deferred tax assets		102,052
Prepaid expenses and other assets	$ 734,524	574,913
Total current assets	33,415,820	36,919,981
Fixed assets
Machinery and equipment	8,840,033	8,604,926
Leasehold improvements	1,539,965	1,524,298
	10,379,998	10,129,224
Less accumulated depreciation and amortization	8,688,285	7,873,816
Net fixed assets	1,691,713	$ 2,255,408
Long-term deferred tax assets	51,188
Marketable securities, long-term	65,695,335	$ 70,913,807
Total assets	100,854,056	110,089,196
Current liabilities
Accounts payable	317,990	358,818
Accrued payroll and other	556,674	$ 1,127,136
Deferred revenue	714,805
Total current liabilities	$ 1,589,469	$ 1,485,954
Long-term deferred tax liabilities		275,708
Shareholders’ equity
Common stock, $0.01 par value, 6,000,000 shares authorized; 4,835,010 issued and outstanding as of March 31, 2016 and 4,857,953 issued and outstanding as of March 31, 2015	$ 48,350	48,580
Additional paid-in capital	19,205,682	20,850,762
Accumulated other comprehensive income	451,359	746,447
Retained earnings	79,559,196	86,681,745
Total shareholders’ equity	99,264,587	108,327,534
Total liabilities and shareholders’ equity	$ 100,854,056	$ 110,089,196