The below table presents the components of the carrying value of the 2025 Notes and the 2027 Notes as of December 31, 2022 and September 30, 2022: | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | As of December 31, 2022 | | As of September 30, 2022 | | ($ in millions) | | 2025 Notes | | 2027 Notes | | 2025 Notes | | 2027 Notes | | Principal | | $ | 300.0 | | | $ | 350.0 | | | $ | 300.0 | | | $ | 350.0 | | | Unamortized financing costs | | (1.6) | | | (3.1) | | | (1.8) | | | (3.2) | | | Unaccreted discount | | (1.1) | | | (0.7) | | | (1.2) | | | (0.7) | | | Interest rate swap fair value adjustment | | — | | | (39.9) | | | — | | | (42.0) | | | Net carrying value | | $ | 297.3 | | | $ | 306.3 | | | $ | 297.0 | | | $ | 304.1 | | | Fair Value | | $ | 286.7 | | | $ | 296.8 | | | $ | 283.1 | | | $ | 294.0 | |
The below table presents the components of interest and other debt expenses related to the 2025 Notes and the 2027 Notes for the three months ended December 31, 2022: | | | | | | | | | | | | | | | | ($ in millions) | | 2025 Notes | | 2027 Notes | | Coupon interest | | $ | 2.6 | | | $ | 2.4 | | | Amortization of financing costs and discount | | 0.3 | | | 0.2 | | | Effect of interest rate swap | | — | | | 2.5 | | | Total interest expense | | $ | 2.9 | | | $ | 5.1 | | | Coupon interest rate (net of effect of interest rate swap for 2027 Notes) | | 3.500 | % | | 5.586 | % |
The below table presents the components of interest and other debt expenses related to the 2025 Notes and the 2027 Notes for the three months ended December 31, 2021: | | | | | | | | | | | | | | | | ($ in millions) | | 2025 Notes | | 2027 Notes | | Coupon interest | | $ | 2.6 | | | $ | 2.4 | | | Amortization of financing costs and discount | | 0.3 | | | 0.2 | | | Effect of interest rate swap | | — | | | (0.7) | | | Total interest expense | | $ | 2.9 | | | $ | 1.9 | | | Coupon interest rate (net of effect of interest rate swap for 2027 Notes) | | 3.500 | % | | 1.782 | % |
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