NOTE 5. STOCK-BASED COMPENSATION: Schedule of Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Grants in Period, Grant Date Intrinsic Value (Details) - USD ($)	12 Months Ended
Mar. 31, 2023	Mar. 31, 2022	Mar. 31, 2021
Details
Options Outstanding	34,500
Options Outstanding, Weighted Average Remaining Contractual Life (Years)	5 years 8 months 1 day
Options Outstanding, Weighted Average Exercise Price	$ 66.26	$ 69.52	$ 68.28
Options Outstanding, Aggregate Intrinsic Value	$ 562,415
Options Exercisable	32,000	24,000
Options Exercisable, Weighted Average Exercise Price	$ 63.60	$ 64.32
Options Exercisable, Aggregate Intrinsic Value	$ 562,415

Weighted average amortization period of finite-lived intangible assets acquired either individually or as part of a group of assets, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Number of equity instruments other than options outstanding, including both vested and non-vested instruments.

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The number of shares into which fully or partially vested stock options outstanding as of the balance sheet date can be currently converted under the option plan.

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Weighted average price at which grantees can acquire the shares reserved for issuance under the stock option plan.

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