Consolidated Statements of Cash Flows (Unaudited) - USD ($)	3 Months Ended
	Aug. 31, 2017	Aug. 31, 2016
Cash Flows from Operating Activities:
Net income	$ 530,282	$ 27,008
Adjustments to reconcile net income to net cash provided by operating activities -
Depreciation and amortization	778,911	527,816
Decrease (Increase) in deferred tax asset	203,800	(18,850)
Decrease in trade accounts receivable	3,731,179	1,030,987
Decrease in related party receivables	36,828	14,492
Increase in inventory	(1,241,534)	(14,003)
Decrease in prepaid expenses	76,983	52,135
Decrease in accounts payable and accrued expenses	(2,023,966)	(330,982)
Net cash provided by operating activities	2,092,483	1,288,603
Cash Flows from Investing Activities:
Purchase of property and equipment	(1,977,498)	(849,062)
Cash Flows from Financing Activities:
Proceeds from long-term debt	1,795,000
Payments on long-term debt and capitalized lease	(1,185,634)	(570,014)
Proceeds from exercised stock options		57,000
Dividends paid on preferred stock	(92,398)	(87,746)
Distributions paid by variable interest entity	(51,000)	(51,000)
Net cash provided by (used in) financing activities	465,968	(651,760)
Net Increase (Decrease) in Cash	580,953	(212,219)
Cash, beginning of year	579,021	897,377
Cash, end of year	1,159,974	685,158
Non-Cash Activities:
Acquisition of equipment by capital lease		2,731,152
Conversion of related party accrued interest to long-term debt		2,475,690
Preferred dividend accrual	31,849	57,329
Supplemental information:
Interest paid	$ 295,836	$ 191,333