CT income tax difference with TAXSIM35

[martinholmer]

The following integration test fails. It is not yet known whether the
tax logic problem is in TAXSIM35 or in the current PEUS code, or
whether there are problems in both models. This topic is meant to
facilitate discussion of why this test fails, primarily by reporting
the results of hand calculations required to fill out the relevant tax
form.

- name: Tax unit with taxsimid 85078 in f21.its.csv and f21.ots.csv
  absolute_error_margin: 0.01
  period: 2021
  input:
    people:
      person1:
        age: 64
        employment_income: 43010
        taxable_interest_income: 11010
        taxable_private_pension_income: 11000
        social_security_retirement: 15000
        ssi: 0  # not in TAXSIM35
        state_supplement: 0  # not in TAXSIM35
        wic: 0  # not in TAXSIM35
        ma_covid_19_essential_employee_premium_pay_program: 0  # not in TAXSIM35
    tax_units:
      tax_unit:
        members: [person1]
        premium_tax_credit: 0  # not in TAXSIM35
        local_income_tax: 0  # not in TAXSIM35
        state_sales_tax: 0  # not in TAXSIM35
        ca_use_tax: 0  # not in TAXSIM35
        il_use_tax: 0  # not in TAXSIM35
        nm_2021_income_rebate: 0  # not in TAXSIM35
        nm_additional_2021_income_rebate: 0  # not in TAXSIM35
        nm_supplemental_2021_income_rebate: 0  # not in TAXSIM35
        ny_supplemental_eitc: 0  # not in TAXSIM35
        ok_use_tax: 0  # not in TAXSIM35
        pa_use_tax: 0  # not in TAXSIM35
        vt_renter_credit: 0  # not in TAXSIM35
    spm_units:
      spm_unit:
        members: [person1]
        snap: 0  # not in TAXSIM35
        tanf: 0  # not in TAXSIM35
    households:
      household:
        members: [person1]
        state_fips: 9  # CT
  output:  # expected results from patched TAXSIM35 2024-02-15 version
    ct_income_tax: 2669.27

[PavelMakarchuk]

@Shinuing I believe the issues here lie in the AGI subtractions could you check everything but the ct_social_security_benefit_adjustment - I am. currently fixing that but it is not the only cause of the diff
TAXSIM attributes an AGI amount of $60,570.63 while PE is higher

[PavelMakarchuk]

@martinholmer while there is still an AGI discrepancy of ~$8,000 in this test case, we are unsure where this error comes from.
The SS deduction is computed as follows:

Form

While the other types of income are not subject to any subtraction as far as we can see.

Unsure whether the ss subtraction calculation differs in TAXSIM but I dont see any other subtraction that could cause this, please let us know if we missed anything in this case

Tax form instructions