	As of September 30, 2019			As of December 31, 2018
Revolving credit facility(A)	$	451,006		$	28,059
USD term loan		200,000			200,000
Australian term loan facility(B)		810,000			—
4.000% Senior Unsecured Notes due 2022(C)		544,950			573,350
5.500% Senior Unsecured Notes due 2024		300,000			300,000
6.375% Senior Unsecured Notes due 2024		500,000			500,000
3.325% Senior Unsecured Notes due 2025(C)		544,950			573,350
5.250% Senior Unsecured Notes due 2026		500,000			500,000
5.000% Senior Unsecured Notes due 2027		1,400,000			1,400,000
4.625% Senior Unsecured Notes due 2029		900,000			—
	$	6,150,906		$	4,074,759
Debt issue costs, net and discount		(54,674	)		(37,370	)
	$	6,096,232		$	4,037,389

As of September 30, 2019, principal payments due on our debt (which exclude the effects of any discounts, premiums, or debt issue costs recorded) are as follows (in thousands):

2019	$	—
2020		—
2021		451,006
2022		744,950
2023		—
Thereafter		4,954,950
Total	$	6,150,906

On July 26, 2019, we completed a $900 million senior unsecured notes offering (“4.625% Senior Unsecured Notes due 2029”). Interest on the notes is payable semi-annually on February 1 and August 1 of each year, commencing on February 1, 2020. The notes were issued at 99.5% of par value, pay interest at a rate of 4.625% per year and mature on August 1, 2029. We may redeem some or all of the notes at any time prior to August 1, 2024 at a “make whole” redemption price. On or after August 1, 2024, we may redeem some or all of the notes at a premium that will decrease over time. In addition, at any time prior to August 1, 2022, we may redeem up to 40% of the notes at a redemption price equal to 104.625% of the aggregate principal amount thereof, plus accrued and unpaid interest thereon, using proceeds from one or more equity offerings. In the event of a change in control, each holder of the notes may require us to repurchase some or all of the notes at a repurchase price equal to 101% of the aggregate principal amount of the notes plus accrued and unpaid interest to the date of purchase.

We used the net proceeds from the 4.625% Senior Unsecured Notes due 2029 offering along with the proceeds from our July 2019 equity offering to finance the Prospect transaction described in Note 3. As a result of these offerings, we canceled the $1.55 billion senior unsecured bridge loan facility commitment from Barclays Bank PLC that we received on July 10, 2019. With this commitment, we paid $4.0 million of underwriting and other fees, which we fully expensed upon the cancellation of the commitment during the 2019 third quarter.

On May 23, 2019, we entered into an AUD$1.2 billion term loan facility agreement with Bank of America, N.A., as administrative agent, and several lenders from time-to-time are parties thereto. The term loan facility matures on May 23, 2024. We used the proceeds under the facility to finance our acquisition of the Healthscope portfolio. The interest rate under the term loan is adjustable based on a pricing grid from 0.85% to 1.65%, dependent on our current senior unsecured credit rating. On June 27, 2019, we entered into an interest rate swap transaction (effective July 3, 2019) to fix the interest rate to approximately 1.20% for the duration of the loan. The current applicable margin for the pricing grid (which can vary based on the Company’s credit rating) is 1.25% for an all-in fixed rate of 2.45%. We paid approximately $8 million in one-time structuring and underwriting fees associated with this term loan facility.

In preparation of the joint venture with Primotop described under “Acquisitions” in Note 3, we issued secured debt on August 3, 2018, resulting in gross proceeds of €655 million. Subsequently, on August 31, 2018, the secured debt was contributed along with the related real estate of 71 properties to form the joint venture. Provisions of the secured debt include a term of seven years and a swapped fixed rate of approximately 2.3%.

Our debt facilities impose certain restrictions on us, including restrictions on our ability to: incur debts; create or incur liens; provide guarantees in respect of obligations of any other entity; make redemptions and repurchases of our capital stock; prepay, redeem or repurchase debt; engage in mergers or consolidations; enter into affiliated transactions; dispose of real estate or other assets; and change our business. In addition, the credit agreements governing our revolving credit and term loan agreement (“Credit Facility”) limit the amount of dividends we can pay as a percentage of normalized adjusted funds from operations, as defined in the agreements, on a rolling four quarter basis. At September 30, 2019, the dividend restriction was 95% of normalized adjusted funds from operations (“NAFFO”). The indentures governing our senior unsecured notes also limit the amount of dividends we can pay based on the sum of 95% of NAFFO, proceeds of equity issuances and certain other net cash proceeds. Finally, our senior unsecured notes require us to maintain total unencumbered assets (as defined in the related indenture) of not less than 150% of our unsecured indebtedness.

In addition to these restrictions, the Credit Facility contains customary financial and operating covenants, including covenants relating to our total leverage ratio, fixed charge coverage ratio, secured leverage ratio, consolidated adjusted net worth, unsecured leverage ratio, and unsecured interest coverage ratio. This Credit Facility also contains customary events of default, including among others, nonpayment of principal or interest, material inaccuracy of representations and failure to comply with our covenants. If an event of default occurs and is continuing under the Credit Facility, the entire outstanding balance may become immediately due and payable. At September 30, 2019, we were in compliance with all such financial and operating covenants.