DC single-joint threshold ratio switch

[nikhilwoodruff]

Fixes #3045

🤖 Generated by Copilot at b35edfe

Summary

📄🛠️🔗

This pull request adds a new reform option for DC's income tax that allows adjusting the tax thresholds for joint filers relative to single filers. The reform is defined by a new parameter, a new function, and a new file in the reforms module.

To model DC's income tax
We added a new parameter ratio
It changes the thresholds
For joint filers' wedges
And creates a reform with a bypass

Walkthrough

• Add a new parameter and a new reform for the ratio of single to joint tax thresholds for DC's income tax (link, link, link, link, link)

• Create a new parameter file dc_tax_threshold_joint_ratio.yaml with a default value of 1, a description, a unit, and a label (link)
• Create a new reform file dc_tax_threshold_joint_ratio.py that defines a function to create a reform class that modifies the dc_income_tax_before_credits variable based on the parameter value (link)
• Import the new reform function in the reforms module (link)
• Call the new reform function in the create_structural_reforms_from_parameters function, which takes a set of parameters and a period and returns a reform (link)
• Add a conditional branch to the create_structural_reforms_from_parameters function that returns the new reform if it is not None, otherwise it continues to check for other reforms (link)

[nikhilwoodruff]

Needs tests

[MaxGhenis]

Also need to ensure it works in conjunction with the repeal of married filing separately on same return; i.e., to check against filing status

[codecov]

Codecov Report

Patch and project coverage have no change.

Comparison is base (7362d43) 98.70% compared to head (997eac7) 98.70%.

Additional details and impacted files

@@           Coverage Diff           @@
##           master    #3046   +/-   ##
=======================================
  Coverage   98.70%   98.70%           
=======================================
  Files        1706     1706           
  Lines       25714    25714           
  Branches      145      145           
=======================================
  Hits        25382    25382           
  Misses        301      301           
  Partials       31       31           

Files Changed	Coverage Δ
...come/deductions/itemized/az_itemized_deductions.py	100.00% <ø> (ø)

☔ View full report in Codecov by Sentry.
📢 Have feedback on the report? Share it here.