policy_current_law.json needs to be updated with 2018 parameters

[MattHJensen]

https://www.irs.gov/pub/irs-drop/rp-17-58.pdf

See last year's update: #1169

[martinholmer]

@MattHJensen asked for help in adding to policy_current_law.json the values of tax policy parameters for 2018.

I know IRS has published 2018 values, but isn't this request pre-mature given that TCJA may change many 2018 values?

[MaxGhenis]

If TCJA goes into effect, will this be irrelevant?

On a related note: if TCJA goes into effect, will there be a way to access current policy? I suspect people will continue to be interested in analyzing TCJA relative to current/previous policy. One option could be adding current policy as a "reform" to the reforms folder. Happy to file a separate issue on this.

[martinholmer]

@MaxGhenis said:

On a related note: if TCJA goes into effect, will there be a way to access current policy? I suspect people will continue to be interested in analyzing TCJA relative to current/previous policy. One option could be adding current policy as a "reform" to the reforms folder.

We haven't discussed this, but passage of the TCJA bill into law will, of course, change the meaning of "current-law policy" and there will probably be a major revision to the contents of the taxcalc/reforms directory. One of the first new reforms to be added would probably be prior_law_policy.json, which would reform the TCJA current-law policy back to the pre-TCJA policy.

[MattHJensen]

Perhaps 2017_law_policy.json or similar, as there may be many "prior laws" in the lifetime of Tax-Calculator.

[martinholmer]

@MattHJensen said in issue #1694 entitled "current_law_policy.json needs to be updated with 2018 parameters":

https://www.irs.gov/pub/irs-drop/rp-17-58.pdf

See last year's update: #1169

Just to confirm my understanding of this issue, the 2018 values in the cited IRS publication are no longer correct given the passage of TCJA. Right?

I assume IRS will soon publish a new document that has 2018 values for the now chained-CPI indexed parameters whose amounts were not explicitly changed by TCJA. We can do this update when that new document is published.

[MattHJensen]

Just to confirm my understanding of this issue, the 2018 values in the cited IRS publication are no longer correct given the passage of TCJA. Right?

That's correct.

I assume IRS will soon publish a new document that has 2018 values for the now chained-CPI indexed parameters whose amounts were not explicitly changed by TCJA. We can do this update when that new document is published.

The IRS just published the new parameters, which are explained and linked to from this KPMG report.

[MattHJensen]

This update will be easier when the 2018 forms are published. Currently a draft 1040 is out, but I believe it is being revised.

[martinholmer]

@Peter-Metz, as I said in this comment a few days ago, your help in resolving issue #1694 would be much appreciated. I've tried to provide more guidance for your work by adding a FAQ on the policy parameter updating process in issue #2183. You can open a pull request now that consists of several small commits, each one of which contains changes in the policy_current_law.json file associated with a single final 2018 IRS form/instructions. So, for example, the first commit would contain just the 2018 values for parameters on the 2018 Form 1040 or in the Form 1040 instructions. The second commit would contain just the 2018 values for parameters on the 2018 Form 2441 or in the Form 2441 instructions. And so forth, until all the parameters are updated with actual 2018 values.

As you go about this work, you can test the coding style of the revised policy_current_law.json file, using this command:

$ pycodestyle --ignore=E501,E121 taxcalc/policy_current_law.json

Also, as you commit the changes associated with each IRS form/instructions, be sure to edit the pull request comment to provide a URL for the IRS PDF file that contains the form and for the IRS PDF file that contains the form instructions.

If you have any questions about how to proceed, pose them here in issue #1694.

@MattHJensen

[Peter-Metz]

@martinholmer, thanks for the clear guidance for what needs to be done.

[martinholmer]

Issue #1694 has been resolved by the merge of pull request #2212.