	December 31,
(in thousands)	2020			2019
Principal balance under First Lien Credit Agreement	$	681,126		$	688,155
Less: Unamortized debt issuance costs and discounts		(14,209	)		(17,233	)
	$	666,917		$	670,922

In October 2018, the Company entered into a First Lien Credit Agreement (“First Lien”) and a Second Lien Credit Agreement (“Second Lien”) with various lenders, for term loans of $545 million and $200 million, respectively. The Second Lien bore interest at a rate equal to the LIBO Screen Rate plus a margin of 7.50% per annum.

In November 2019, the Company entered into an amendment of the First Lien to draw an additional term loan in the amount of $155 million. The additional term loan has the same maturity date and other terms as the original $545 million term loan. The proceeds from the amendment to the First Lien and existing cash resources were used to repay the Second Lien including prepayment penalties. The Company recognized a loss on extinguishment of the Second Lien of $4.9 million from unamortized debt issuance costs and discounts and prepayment penalties. The Company incurred third-party costs related to the amendment of the First Lien of $2.9 million which were expensed as incurred in other expense, net in the consolidated statements of operations.

The First Lien accrues interest at a rate per annum equal to the LIBO Screen Rate plus a variable margin based on the Company’s most recently determined Net Leverage Ratio (as defined in the First Lien Credit Agreement), ranging from 2.75% to 3.00%. The effective interest rate on the First Lien for the years ended December 31, 2020 and 2019 was 3.97% and 5.90%, respectively. The First Lien requires quarterly principal payments from March 2019 through September 2025, with any remaining unpaid principal and any accrued and unpaid interest due on the maturity date of October 10, 2025. The Company may prepay the First Lien without penalty after April 2019. The First Lien is collateralized by substantially all of the assets of the Company and 100% of the equity interest of GoodRx.

As of December 31, 2020, the Company is subject to a financial covenant requiring maintenance of a Net Leverage Ratio not to exceed 8.2 to 1.0 and other nonfinancial covenants under the First Lien. Additionally, GoodRx is restricted from making dividend payments, loans or advances to the Company. At December 31, 2020, the Company was in compliance with its covenants.

The following table presents details of the future principal payments under the debt agreements at December 31, 2020:

(in thousands)
Year Ending December 31,
2021	$	7,029
2022		7,029
2023		7,029
2024		7,029
2025		653,010
Total principal payments	$	681,126

In 2019, the Company incurred debt issuance costs and discounts of $0.6 million relating to the amendment of the First Lien and the issuance the Second Lien. Amortization of debt issuance costs and discounts of $3.0 million, $3.3 million and $0.8 million were recognized as interest expense in the consolidated statements of operations for the years ended December 31, 2020, 2019 and 2018, respectively.

In October 2018, the Company also obtained a line of credit for up to $40.0 million. During the year ended December 31, 2019, the term of line of credit was extended by one year expiring on October 11, 2024. The line of credit bears interest at a rate equal to the LIBO Screen Rate plus a variable margin based on the Company’s most recently determined Net Leverage Ratio (as defined in the First Lien Credit Agreement), ranging from 2.50 to 3.00% on used amounts and 0.25 to 0.50% on unused amounts. In addition, the line of credit has a fixed fronting fee of 0.125% per annum of the Company’s aggregate undrawn and disbursed but unreimbursed letters of credit. There were no borrowings against the line of credit as of December 31, 2020 and 2019. There were outstanding letters of credit issued against the line of credit for $9.1 million as of December 31, 2020 and 2019, respectively, which reduces the Company’s available borrowings under the line of credit.

In 2019, the Company was required to provide a $9.0 million letter of credit for the benefit of the landlord of a new facility lease which the landlord may draw upon in the event of the Company’s default of rent payment or damages to the building. The letter of credit will decrease by $0.9 million per year commencing in 2023.

In May 2020, GoodRx, Inc., the Company’s wholly owned subsidiary, as borrower, and GoodRx Intermediate Holdings, LLC, entered into an amendment to increase the amount of the line of credit by $60.0 million to a total of $100.0 million. The Company incurred lender and third-party costs of $1.3 million related to the amendment which are recorded in other assets.

The Company borrowed an aggregate of $28.0 million under its line of credit during the year ended December 31, 2020, of which all had been repaid as of December 31, 2020.

Regulatory authorities that oversee financial markets have announced that after the end of 2021, they would no longer compel banks currently reporting information used to set the LIBO Screen Rate to continue to make rate submissions. As a result, it is possible that beginning in 2022, the LIBO Screen Rate will no longer be available as a reference rate. Under the terms of the Company's First Lien Credit Agreement and line of credit, in the event of the discontinuance of the LIBO Screen Rate, a mutually agreed-upon alternate benchmark rate will be established to replace the LIBO Screen Rate. The Company and lenders under its First Lien Credit Agreement and line of credit shall in good faith establish an alternate benchmark rate which places the lenders and the Company in the same economic position that existed immediately prior to the discontinuation of the LIBO Screen Rate. The Company does not anticipate that the discontinuance of the LIBO Screen Rate will materially impact its liquidity or financial position.