Note 2 - Summary of Significant Accounting Policies (Tables)

6 Months Ended

Dec. 31, 2018

Notes Tables

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

	Three Months Ended December 31 , 2018				Three Months Ended December 31 , 2017
	Revenue				Revenue
Fund
USO	$	1,853,481	47	%	$	2,499,615	52	%
USCI		1,095,830	28	%		979,375	20	%
UNG		572,526	14	%		874,162	18	%
All Others		417,167	11	%		492,472	10	%
Total	$	3,939,004	100	%	$	4,845,624	100	%

	Six Months Ended December 31, 2018				Six Months Ended December 31, 2017
	Revenue				Revenue
Fund
USO	$	3,838,402	47	%	$	5,443,460	54	%
USCI		2,349,689	29	%		1,957,993	20	%
UNG		1,077,388	13	%		1,572,018	16	%
All Others		896,509	11	%		1,030,101	10	%
Total	$	8,161,988	100	%	$	10,003,572	100	%

	December 3 1 , 2018				June 30, 2018
	Accounts Receivable				Accounts Receivable
Fund
USO	$	583,979	47	%	$	674,535	46	%
USCI		334,497	27	%		431,288	30	%
UNG		180,633	15	%		182,399	12	%
All Others		132,673	11	%		169,937	12	%
Total	$	1,231,782	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