Investments consist of the following as of June 30, 2019 and December 31, 2018 (dollars in thousands):

	June 30, 2019
			Gross Unrealized
	Cost		Gain		(Loss)			Fair Value
Short-term investments (available for sale):
Municipal bonds	$	628	$	1	$	-		$	629
Non-governmental debt securities		212,175		420		(28	)		212,567
Treasury and federal agencies		15,606		6		(13	)		15,599
Total short-term investments (available for sale)	$	228,409	$	427	$	(41	)	$	228,795

	December 31, 2018
			Gross Unrealized
	Cost		Gain		(Loss)			Fair Value
Short-term investments (available for sale):
Non-governmental debt securities	$	179,393	$	35	$	(337	)	$	179,091
Treasury and federal agencies		17,417		5		(85	)		17,337
Total short-term investments (available for sale)	$	196,810	$	40	$	(422	)	$	196,428

In the table above, unrealized holding gains (losses) relate to short-term investments that have been in a continuous unrealized gain (loss) position for less than one year.

Our non-governmental debt securities primarily consist of commercial paper and certificates of deposit. Our treasury and federal agencies primarily consist of U.S. Treasury bills and federal home loan debt securities. We do not intend to sell our investments in these securities prior to maturity and it is not likely that we will be required to sell these investments before recovery of the amortized cost basis.

FASB ASC Topic 820 – Fair Value Measurements establishes a three-tier fair value hierarchy, which prioritizes the inputs used in measuring fair value. These tiers include: Level 1, defined as observable inputs such as quoted prices in active markets; Level 2, defined as inputs other than quoted prices in active markets that are either directly or indirectly observable; and Level 3, defined as unobservable inputs in which little or no market data exists, therefore requiring an entity to develop its own assumptions.

As of June 30, 2019, we held investments that are required to be measured at fair value on a recurring basis. These investments (available-for-sale) consist of municipal bonds, non-governmental debt securities and treasury and federal agencies securities. Available for sale securities included in Level 1 are valued at quoted prices in active markets for identical assets and liabilities. Available for sale securities included in Level 2 are estimated based on observable inputs other than quoted prices in active markets for identical assets and liabilities, such as quoted prices for identical or similar assets or liabilities in inactive markets or other inputs that are observable or can be corroborated by observable market data for substantially the full term of the assets or liabilities.

Investments measured at fair value on a recurring basis subject to the disclosure requirements of FASB ASC Topic 820 – Fair Value Measurements at June 30, 2019 and December 31, 2018 were as follows (dollars in thousands):

	As of June 30, 2019
	Level 1		Level 2		Level 3		Total
Municipal bonds	$	-	$	629	$	-	$	629
Non-governmental debt securities		20,000		192,567		-		212,567
Treasury and federal agencies		-		15,599		-		15,599
Totals	$	20,000	$	208,795	$	-	$	228,795

	As of December 31, 2018
	Level 1		Level 2		Level 3		Total
Non-governmental debt securities	$	20,000	$	159,091	$	-	$	179,091
Treasury and federal agencies		-		17,337		-		17,337
Totals	$	20,000	$	176,428	$	-	$	196,428

Our investment in an equity affiliate, which is recorded within other noncurrent assets on our condensed consolidated balance sheets, represents an international investment in a private company. As of June 30, 2019, our investment in an equity affiliate equated to a 30.7%, or $2.7 million, non-controlling interest in CCKF, a Dublin-based educational technology company providing intelligent systems to power the delivery of individualized and personalized learning.

During the quarters ended June 30, 2019 and 2018, we recorded less than $0.1 million of gain and approximately $0.2 million of loss, respectively, and during the years to date ended June 30, 2019 and June 30, 2018, we recorded less than $0.1 million of gain and approximately $0.1 million of loss, respectively, related to our proportionate investment in CCKF within miscellaneous income (expense) on our unaudited condensed consolidated statements of (loss) income and comprehensive (loss) income.

We make periodic operating maintenance payments related to proprietary rights that we use in our intellipath^® personalized learning technology. The total fees paid to CCKF for the quarters and years to date ended June 30, 2019 and 2018 were as follows (dollars in thousands):

On December 27, 2018, the Company; its wholly-owned subsidiary, CEC Educational Services, LLC; and the subsidiary guarantors thereunder, entered into a credit agreement with BMO Harris Bank N.A. (“BMO Harris”), in its capacities as the sole lender, the letter of credit issuer thereunder and the administrative agent for the lenders which from time to time may be parties to the credit agreement. The credit agreement provides the Company with the benefit of a $50.0 million revolving credit facility and is scheduled to mature on January 20, 2022. The loans and letter of credit obligations under the credit agreement are required to be 100% secured with cash and marketable securities deposited with the bank. As of June 30, 2019 and December 31, 2018, there were no outstanding borrowings under the revolving credit facility.