5. FAIR VALUE OF FINANCIAL INSTRUMENTS (Tables)

9 Months Ended

Feb. 28, 2018

Fair Value Disclosures [Abstract]

Fair value by hierarchy

   The following table summarizes the Company’s financial assets measured at fair value on a recurring basis as of February 28, 2018 (in thousands):

	Balance as of
	February 28, 2018		Level 1		Level 2		Level 3
Money market funds	$	7,178	$	7,178	$	--	$	--
U.S. Treasury securities		5,986		5,986		--		--
Certificate of deposit		80		--		80		--
Assets	$	13,244	$	13,164	$	80	$	--

    The U.S. Treasuary Securities have maturities of six months.

    The following table summarizes the Company’s financial assets measured at fair value on a recurring basis as of May 31, 2017 (in thousands):

	Balance as of
	May 31, 2017		Level 1		Level 2		Level 3
Money market funds	$	15,516	$	15,516	$	--	$	--
Certificate of deposit		50		--		50		--
Assets	$	15,566	$	15,516	$	50	$	--