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Municipal Bond Guarantee Insurance (Tables) | 12 Months Ended
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Dec. 31, 2022
Insurance [Abstract] |
Schedule of Insured Obligations | The following table presents a schedule of BAM’s insured obligations as of December 31, 2022 and 2021:
|  | December 31,
|  | 2022 |  | 2021
Contracts outstanding |  | 13,382 |  | 12,350
Remaining weighted average contract period (in years) |  | 10.8 |  | 10.8
Contractual debt service outstanding (in millions): |  |  |  |
Principal |  | $ | 99,996.9 |  |  | $ | 89,196.5 |
Interest |  | 48,880.6 |  |  | 41,486.5 |
Total debt service outstanding |  | $ | 148,877.5 |  |  | $ | 130,683.0 |
Gross unearned insurance premiums (in millions) |  | $ | 298.3 |  |  | $ | 266.3 |
Schedule of BAM’s future premium revenues | The following table presents a schedule of BAM’s future premium revenues as of December 31, 2022:
Millions |  | December 31, 2022
January 1, 2023 - March 31, 2023 |  | $ | 7.0 |
April 1, 2023 - June 30, 2023 |  | 7.0 |
July 1, 2023 - September 30, 2023 |  | 6.8 |
October 1, 2023 - December 31, 2023 |  | 6.7 |
|  | 27.5 |
2024 |  | 25.9 |
2025 |  | 24.2 |
2026 |  | 22.6 |
2027 |  | 21.0 |
2028 and thereafter |  | 177.1 |
Total gross unearned insurance premiums |  | $ | 298.3 |
Schedule of Net Written Premiums | The following table presents a schedule of written premiums and earned premiums included in White Mountains’s HG Global/BAM segment for the years ended December 31, 2022, 2021 and 2020:
|  | December 31,
Millions |  | 2022 |  | 2021 |  | 2020
Written premiums: |  |  |  |  |  |
Direct |  | $ | 63.8 |  |  | $ | 51.0 |  |  | $ | 61.5 |
Assumed |  | 1.3 |  |  | 4.6 |  |  | .2 |
Gross written premiums (1) |  | $ | 65.1 |  |  | $ | 55.6 |  |  | $ | 61.7 |
Earned premiums: |  |  |  |  |  |
Direct |  | $ | 28.6 |  |  | $ | 23.2 |  |  | $ | 19.4 |
Assumed |  | 4.7 |  |  | 3.7 |  |  | 3.4 |
Gross earned premiums (1) |  | $ | 33.3 |  |  | $ | 26.9 |  |  | $ | 22.8 |
(1) There are no ceded premium amounts in the periods presented and Gross earned premium are equivalent to net written premiums and net earned premiums.

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- Definition Tabular disclosure of financial guarantee insurance contracts in which premiums are received over the contract period. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 310 -Section 50 -Paragraph 3 -URI https://asc.fasb.org/extlink&oid=6933075&loc=SL5748726-161290 + Details
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