Note 8 - Debt - Continued Interest Paid Credit Facilities Note 9 - Employee Benefit Plans Defined Benefit Pension and Other Postretirement Benefit (OPEB) Plans U.S. Pension Plan Annuity Purchases Interest paid on long-term and short-term debt and related securities during 2020, 2019, and 2018 was $178.1 million, $172.9 million, and $167.3 million, respectively. We have access to two separate unsecured revolving credit facilities, each with a different syndicate of lenders. One of our credit facilities is under a five-year agreement and is effective through April 2024. The terms of this agreement provide for a borrowing capacity of $500.0 million with an option to be increased up to $700.0 million. We may also request, on up to two occasions, that the lenders' commitment termination dates be extended by one year. The credit facility provides for the issuance of letters of credit subject to certain terms and limitations. At December 31, 2020, letters of credit totaling $0.6 million had been issued from this credit facility, but there were no borrowed amounts outstanding. Our other credit facility is under a three-year agreement and is effective until April 2022. The terms of this agreement provide for a borrowing capacity of $100.0 million with an option to be increased up to $140.0 million. We may also request that the lenders' commitment termination dates be extended by one year. The credit facility provides for the issuance of letters of credit subject to certain terms and limitations. At December 31, 2020, there have been no letters of credit issued from the credit facility and there were no borrowed amounts outstanding. Borrowings under the credit facilities are for general corporate uses and are subject to financial covenants, negative covenants, and events of default that are customary. The two primary financial covenants include limitations based on our leverage ratio and consolidated net worth. We are also subject to covenants that limit subsidiary indebtedness. The credit facilities provide for borrowings at an interest rate based either on the prime rate or LIBOR. We sponsor several defined benefit pension and OPEB plans for our employees, including non-qualified pension plans. The U.S. qualified and non- qualified defined benefit pension plans comprise the majority of our total benefit obligation and benefit cost. We maintain a separate defined benefit plan for eligible employees in our U.K. operation. The U.S. defined benefit pension plans were closed to new entrants on December 31, 2013, the OPEB plan was closed to new entrants on December 31, 2012, and the U.K. plan was closed to new entrants on December 31, 2002. On December 26, 2019, we purchased a group annuity contract which transferred a portion of our U.S. qualified defined benefit pension plan obligation to a third party. Under the transaction, which was funded with plan assets, we transferred the responsibility for pension benefits and annuity administration for approximately 1,900 retirees or their beneficiaries receiving less than $350 in monthly benefit payments from the plan. This transfer resulted in a reduction in our U.S. qualified defined benefit pension plan obligation of $59.5 million at December 31, 2019 and is reflected in the Benefits and Expenses Paid line item within the following table regarding changes in our benefit obligation. On January 2, 2020, in a separate transaction, we purchased a second group annuity contract which transferred an additional portion of our U.S. qualified defined benefit pension plan obligation to the same third party. Under the transaction, which was funded with plan assets, we transferred the responsibility for pension benefits and annuity administration for approximately 600 retirees or their beneficiaries receiving between $350 and $500 in monthly benefit payments from the plan. This transfer resulted in a reduction in our U.S. qualified benefit pension plan obligation of $44.0 million at December 31, 2020 and is reflected in the Benefits and Expenses Paid line item within the following table regarding changes in our benefit obligation. 180 NOTES TO CONSOLIDATED FINANCIAL STATEMENTS - Continued Unum Group and Subsidiaries