Balance Sheets (Current Period Unaudited) - USD ($)	Mar. 31, 2023	Dec. 31, 2022
Current assets:
Accounts receivable	$ 77,413	$ 126,423
Prepaid expense and other assets	130,966	28,695
Total current assets	8,413,715	8,307,928
Property and equipment, net	9,095,905	9,079,612
Deferred tax asset	379,262	300,050
Total assets	17,888,882	17,687,590
Current liabilities:
Trade payables and accrued expenses	30,937	37,626
Unearned revenue	148,700	229,550
Total current liabilities	179,637	267,176
Stockholders' equity:
Common stock, 3,000,000 shares authorized, no par value, 1,988,701 and 1,974,427 shares issued and outstanding, respectively, as of March 31, 2023, and December 31, 2022	59,335	59,335
Additional paid in capital	2,835,007	2,308,537
Treasury stock, 10,166 shares, at cost	(176,592)	(176,592)
Retained earnings	14,991,495	15,229,134
Total stockholders' equity	17,709,245	17,420,414
Total liabilities and stockholders' equity	17,888,882	17,687,590
Cash and Cash Equivalents Excluding Certificates of Deposit [Member]
Current assets:
Cash and cash equivalents	7,190,450	7,148,207
Certificates of Deposit [Member]
Current assets:
Cash and cash equivalents	$ 1,014,886	$ 1,004,603