Note 2 - Summary of Significant Accounting Policies (Tables)

9 Months Ended

Mar. 31, 2019

Notes Tables

Schedules of Concentration of Risk, by Risk Factor [Table Text Block]

	Three Months Ended March 31, 201 9				Three Months Ended March 31, 201 8
	Revenue				Revenue
Fund
USO	$	1,803,427	51	%	$	2,187,506	50	%
USCI		912,419	25	%		1,038,924	24	%
UNG		432,915	12	%		648,691	15	%
All Others		418,941	12	%		470,113	11	%
Total	$	3,567,702	100	%	$	4,345,234	100	%

	Nine Months Ended March 31, 201 9				Nine Months Ended March 31, 201 8
	Revenue				Revenue
Fund
USO	$	5,641,829	48	%	$	7,630,965	53	%
USCI		3,262,108	28	%		2,996,917	21	%
UNG		1,510,303	13	%		2,220,710	16	%
All Others		1,315,449	11	%		1,500,214	10	%
Total	$	11,729,689	100	%	$	14,348,806	100	%

	March 31, 201 9				June 30, 201 8
	Accounts Receivable				Accounts Receivable
Fund
USO	$	598,810	49	%	$	674,535	46	%
USCI		309,916	26	%		431,288	30	%
UNG		142,351	12	%		182,399	12	%
All Others		156,284	13	%		169,937	12	%
Total	$	1,207,361	100	%	$	1,458,159	100	%

Property, Plant and Equipment, Estimated Useful Life [Table Text Block]

Category	Estimated Useful Life (in years)
Plant and equipment:	5	to	10
Furniture and office equipment:	3	to	5
Vehicles	3	to	5

Schedule of New Accounting Pronouncements and Changes in Accounting Principles [Table Text Block]

	ASU 2016-01			ASC 606		Total
Increase (decrease):
Assets	$	-		$	-	$	-
Liabilities	$	-		$	-	$	-
Accumulated other comprehensive income	$	(279,951	)	$	-	$	(279,951	)
Retained earnings	$	279,951		$	-	$	279,951