Add param for switching stacking order of dependent credit and ctc

[MattHJensen]

Resolves #1671 following recommendation by @codykallen.

See results.json which shows that stacking dependent credit above ctc does reduce tax liabilities as is expected based on the discussion in #1671.

cc @evtedeschi3 @martinholmer

[codecov-io]

Codecov Report

Merging #1676 into master will not change coverage.
The diff coverage is n/a.

@@          Coverage Diff           @@
##           master   #1676   +/-   ##
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  Coverage     100%    100%           
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  Files          37      37           
  Lines        2856    2856           
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  Hits         2856    2856

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[martinholmer]

@MattHJensen said in pull request #1676:

Resolves #1671 following recommendation by @codykallen.

See results.json which shows that stacking dependent credit above CTC does reduce tax liabilities as is expected based on the discussion in #1671.

I haven't been following this issue closely, but I thought #1671 was about how the CTC and the Additional CTC interacted. What does the stacking order of the "dependent credit" and the nonrefundable CTC have to do with #1671? As you can see, I'm confused and need help understanding this issue. If the pull request does not produce the expected results, maybe we need to think about this issue some more.

[MattHJensen]

I haven't been following this issue closely, but I thought #1671 was about how the CTC and the Additional CTC interacted. What does the stacking order of the "dependent credit" and the nonrefundable CTC have to do with #1671?

Under current law the maximum CTC is $1000 and up to $1000 can flow through to the ACTC for refundability. The TCJA adds to the CTC an amount that can not flow to the ACTC for refundability. We have been modeling that amount with a parameter that we call the Nonrefundable credit for children, on top of the child tax credit There is also a nonrefundable credit for non-children dependents that is treated similarly. The naming here is definitely somewhat confusing, and perhaps if this is enacted we should rethink it (or beforehand), but no one yet has suggested a better approach.

If the pull request does not produce the expected results, maybe we need to think about this issue some more.

The pull request does produce the expected result.

[martinholmer]

@MattHJensen said:

The pull request does produce the expected result.

Right. Sorry, I misread your original comment in pull request #1676.