On February 16, 2021, NuStar Logistics amended its $1.0 billion revolving credit agreement due October 27, 2023 (the Revolving Credit Agreement) to, among other things, expand certain adjustments related to our maximum consolidated debt coverage ratio and minimum consolidated interest coverage ratio.

As of June 30, 2021, we had $185.0 million of borrowings outstanding and $809.8 million available for borrowing under the Revolving Credit Agreement. Letters of credit issued under the Revolving Credit Agreement totaled $5.2 million as of June 30, 2021 and limit the amount we can borrow under the Revolving Credit Agreement. Obligations under the Revolving Credit Agreement are guaranteed by NuStar Energy and NuPOP. The Revolving Credit Agreement provides for U.S. dollar borrowings, which bear interest, at our option, based on an alternative base rate or a LIBOR-based rate. The interest rate on the Revolving Credit Agreement is subject to adjustment if our debt rating is downgraded (or upgraded) by certain credit rating agencies. As of June 30, 2021, our weighted-average interest rate related to borrowings under the Revolving Credit Agreement was 2.6%.

The Revolving Credit Agreement is subject to maximum consolidated debt coverage ratio and minimum consolidated interest coverage ratio requirements, which may limit the amount we can borrow under the Revolving Credit Agreement to an amount less than the total amount available for borrowing. For the rolling period of four quarters ended June 30, 2021, the consolidated debt coverage ratio (as defined in the Revolving Credit Agreement) could not exceed 5.00-to-1.00 and the consolidated interest coverage ratio (as defined in the Revolving Credit Agreement) must not be less than 1.75-to-1.00. As of June 30, 2021, we believe that we are in compliance with the covenants in the Revolving Credit Agreement.

On April 19, 2020, NuStar Energy and NuStar Logistics entered into an unsecured term loan credit agreement with certain lenders and Oaktree Fund Administration, LLC, as administrative agent for the lenders. The Term Loan provided for an aggregate commitment of up to $750.0 million pursuant to a three-year unsecured term loan credit facility. NuStar Logistics drew $500.0 million on April 21, 2020, which we repaid on September 16, 2020. On February 16, 2021, we terminated the Term Loan.

NuStar Energy and NuStar Finance LLC (NuStar Finance), a special purpose entity and wholly owned subsidiary of NuStar Energy, are parties to a $100.0 million receivables financing agreement with a third-party lender (the Receivables Financing Agreement) and agreements with certain of NuStar Energy’s wholly owned subsidiaries (collectively with the Receivables Financing Agreement, the Securitization Program). NuStar Energy provides a performance guarantee in connection with the Securitization Program. NuStar Finance’s sole activity consists of purchasing receivables from NuStar Energy’s subsidiaries that participate in the Securitization Program and providing these receivables as collateral for NuStar Finance’s revolving borrowings under the Securitization Program. NuStar Finance is a separate legal entity and the assets of NuStar Finance, including these accounts receivable, are not available to satisfy the claims of creditors of NuStar Energy, its subsidiaries selling receivables under the Securitization Program or their affiliates. The amount available for borrowing is based on the availability of eligible receivables and other customary factors and conditions.

Borrowings by NuStar Finance under the Receivables Financing Agreement bear interest at the applicable bank rate, as defined under the Receivables Financing Agreement. The weighted average interest rate related to outstanding borrowings under the Securitization Program as of June 30, 2021 was 2.3%. As of June 30, 2021, $125.4 million of our accounts receivable was included in the Securitization Program. The amount of borrowings outstanding under the Receivables Financing Agreement totaled $74.2 million as of June 30, 2021.

We have estimated the fair value of our publicly traded notes based upon quoted prices in active markets; therefore, we determined that the fair value of our publicly traded notes falls in Level 1 of the fair value hierarchy. With regard to our other debt, for which a quoted market price is not available, we have estimated the fair value using a discounted cash flow analysis using current incremental borrowing rates for similar types of borrowing arrangements and determined that the fair value falls in Level 2 of the fair value hierarchy. The carrying amount includes net fair value adjustments, unamortized discounts and unamortized debt issuance costs.