Total ctc_qualifying_children is too coarse for CTC reform accuracy.
Recent artifact comparison makes that clear:
- April 9, 2026 artifact
1.75.5_a84b8824_20260409_111915: ctc_qualifying_children = 67.144M, CTC reform ctc_value delta +$56.307B.
- April 10, 2026 artifact
1.75.7_f7026898_20260410_011801: ctc_qualifying_children = 65.976M, CTC reform ctc_value delta +$74.234B.
The overall qualifying-child count moved down while the reform effect moved up sharply. That suggests the missing margin is child composition, not just child count.
Proposal
Add calibration / validation targets for CTC-relevant child composition, especially:
- qualifying children under age 6 vs ages 6-17
- tax units with 1, 2, and 3+ qualifying children
- corresponding recipient-count diagnostics where possible
These margins matter directly for ARPA-style reforms and other proposals with age-specific or per-child design changes.
Success criteria
- We can report current-law deviations for under-6 vs 6-17 qualifying children and for 1 / 2 / 3+ child tax units.
- CTC reform estimates are less sensitive to adjacent ECPS recalibrations even when total child counts are similar.
Total
ctc_qualifying_childrenis too coarse for CTC reform accuracy.Recent artifact comparison makes that clear:
1.75.5_a84b8824_20260409_111915:ctc_qualifying_children = 67.144M, CTC reformctc_valuedelta+$56.307B.1.75.7_f7026898_20260410_011801:ctc_qualifying_children = 65.976M, CTC reformctc_valuedelta+$74.234B.The overall qualifying-child count moved down while the reform effect moved up sharply. That suggests the missing margin is child composition, not just child count.
Proposal
Add calibration / validation targets for CTC-relevant child composition, especially:
These margins matter directly for ARPA-style reforms and other proposals with age-specific or per-child design changes.
Success criteria