Backfill California SSI/SSP payment standards for 2008-2024 and remove the CAPI federal-rate floor #10480

Problem

The California state supplement payment standard parameters (gov.states.ca.cdss.state_supplement.payment_standard: aged or disabled single and married, blind single and married, dependent, food allowances, out-of-home care and medical care facility) hold the 1991 Welfare and Institutions Code 12200 totals until 2025. From 2008 those totals are below the federal benefit rate. Every pre-2025 SSI/SSP standard is therefore understated by the whole state supplement, both for the state supplement itself and for CAPI, which equals SSI/SSP (WIC 18941).

Examples:

#10379 floors the CAPI standards at the federal benefit rate as a stopgap. The model then pays at least the federal rate, as SSI alone would, but it still leaves out the state supplement in every year before 2025. Its tests pin these known-low values (ca_capi_payment_standard.yaml Cases 14 and 15, and the 2024 case in ca_capi.yaml).

Plan

1. Backfill the payment standard totals for 2008-2024 from the CDSS All County Information Notices (each January's SSI/SSP and CAPI payment standards, and the June 1, 2019 increase) and the archived POMS SI 01415.05x California tables (for example SI 01415.056 for 2024).
2. Delete the federal-rate floor in policyengine_us/variables/gov/states/ca/cdss/capi/_ca_capi_ssi_ssp_standard.py.
3. Restate the pinned pre-2025 tests with the published standards.

Related

• Backdate California State Supplement (SSP) parameters #7787 (draft PR to backdate the California state supplement parameters; it conflicts with main)
• Refactor the California state supplement: state-share parameters and person-level amounts #7892 (state supplement structure: combined totals, facility allowances)
• Pay California CAPI from the SSI/SSP standard per person, with spouse-to-spouse deeming #10379 (CAPI at the SSI/SSP standard; adds the floor)