Available-For-Sale Debt Securities – In connection with certain services provided by our payroll operations, we collect funds from our clients’ accounts in advance of paying client obligations. These funds held for clients are segregated and invested in accordance with our investment policy, which requires all investments carry an investment grade rating at the time of initial investment. These investments, primarily consisting of corporate and municipal bonds and US treasury bills, are classified as available-for-sale and are included in the “Funds held for clients” line item on the accompanying Consolidated Balance Sheets. The par value of these investments totaled $45.3 million and $58.9 million at March 31, 2020 and December 31, 2019, respectively. These bonds have maturity or callable dates ranging from April 2020 through November 2024.

At March 31, 2020, unrealized losses on the securities totaling $0.4 million have not been recognized as a credit loss because the bonds are investment grade quality and management is not required or does not intend to sell prior to an expected recovery in value. The bond issuers continue to make timely principal and interest payments.

The following table summarizes our bond activity for the three months ended March 31, 2020 and the twelve months ended December 31, 2019 (in thousands):

	Three Months Ended			Twelve Months Ended
	March 31, 2020			December 31, 2019
Fair value at beginning of period	$	60,659		$	56,556
Purchases		3,447			27,216
Sales		(13,768	)		(1,686	)
Maturities and calls		(3,350	)		(22,272	)
Change in bond premium		(343	)		(460	)
Fair market value adjustment		(797	)		1,305
Fair value at end of period	$	45,848		$	60,659

In addition to the available-for-sale securities discussed above, we also hold certificates of deposit and other depository assets in the amount of $2.0 million and $2.5 million at March 31, 2020 and December 31, 2019, respectively, related to the funds held for clients.

Interest Rate Swaps – We utilize interest rate swaps to manage interest rate risk exposure associated with our floating-rate debt under the 2018 credit facility, or the forecasted acquisition of such liability. We do not purchase or hold any derivative instruments for trading or speculative purposes.

In March 2020, we entered into a forward starting swap with a notional amount of $50 million. Refer to the Annual Report on Form 10-K for the year ended December 31, 2019 for further discussion on our interest rate swaps.

Under the terms of the interest rate swaps, we pay interest at a fixed rate of interest plus applicable margin as stated in the agreement, and receive interest that varies with the one-month LIBOR. The notional value, fixed rate of interest and expiration date of each interest rate swap as of March 31, 2020 was (i) $25 million – 1.300% – October 2020, (ii) $10 million – 1.120% – February 2021, (iii) $20 million – 1.770% – May 2022 (iv) $15 million – 2.640% – June 2023 and (v) $50 million – 0.885% – April 2025. Refer to Note 7, Fair Value Measurements, for additional disclosures regarding fair value measurements.

The following table summarizes our outstanding interest rate swaps and their classification in the accompanying Consolidated Balance Sheets at March 31, 2020 and December 31, 2019 (in thousands):

	March 31, 2020
	Notional		Fair
	Amount		Value			Balance Sheet Location
Interest rate swaps	$	35,000	$	(178	)	Other current liabilities
Interest rate swaps	$	35,000	$	(1,706	)	Other non-current liabilities
Interest rate swap	$	50,000	$	492		Other non-current assets
	December 31, 2019
	Notional		Fair
	Amount		Value			Balance Sheet Location
Interest rate swaps	$	45,000	$	(591	)	Other non-current liabilities
Interest rate swap	$	25,000	$	66		Other current assets

The following table summarizes the effects of the interest rate swap on our accompanying Consolidated Statements of Comprehensive Income for the three months ended March 31, 2020 and 2019 (in thousands):

	Loss Recognized in AOCL, Net of Tax						(Loss) Gain Reclassified from AOCL into Expense
	Three Months Ended						Three Months Ended
	March 31,						March 31,
	2020			2019			2020			2019
Interest rate swaps	$	(653	)	$	(427	)	$	(34	)	$	139