Allow ind inc and fica tax param inputs in CCC

[jdebacker]

B-Tax integrates with the Tax Calculator. This PR is to suggest we allow inputs for IIT parameters on CCC.

There are a few options to do this. e.g.,: 1) A link to Tax Brain to enter full list of parameters 2) Allow a limited set of parameters to be entered in CCC itself (e.g. rates on dividends and capital gains, pass-through business income, etc.). 3) A mix of (1) and (2)

It might be easiest to start with (2) and go from there.

[MattHJensen]

FYI, #295 provides some history of thought.

[MattHJensen]

Back in #295, this comment described the long run goals as:

1. Some subset of parameters from TC are displayed on the Cost of Capital Calculator (CCC) input page. (@jdebacker will provide this list)
2. There is unfolding/expansion option on the CCC input page that allows the CCC user to see all of the TC params that are currently available on TB.
3. On the TB static results page, there is a "Link to Cost of Capital Calculator" button right next to the "Link to Dynamic Simulations".

@jdebacker, what do you think about constraining this issue to step 1. Specifically, this would entail including all parameters from TaxBrain's Regular Tax, AMT, and Other Taxes sections under an individual income tax section on the CCC input page.

I also propose replacing the second goal with a TC parameter file upload feature.

We then will need a separate issue for the parameter file upload feature and for the third goal.

[jdebacker]

@MattHJensen - yes, I think constrain to "step 1" makes sense. This is my suggestion in the first comment here.

I do think that when this is done, it would be nice to group the parameters ways so that the inputs don't seem overwhelming. This could be done by using indentation for the sections noted in the column on the left of the screen. E.g.:

Individual Income Tax
    Regular Tax
    AMT
    Other Taxes
Business Taxes
    Business Income Tax Rates
    Depreciation
    Other
Macroeconomic Assumptions

Or (much more complicated) one could have these grouping expand on the main screen (e.g. you scroll down from the top to the Individual Tax Section and you see "+Regular Tax" - if you click the "+" it'll then expand and allow you to adjust the default values.

I like your idea for json upload vs expanding list. I think that's a suitable substitute for step 2 - especially if we eventually get to step 3.

One complication we might want consistency in macro assumptions. I think we are using different interest rates between CCC and TB, but the inflation rates should be consistent. But my suggestion is to just get these two integrated and then we can workout this minor issue later.

[MattHJensen]

This could be done by using indentation for the sections noted in the column on the left of the screen. E.g.:

Individual Income Tax
    Regular Tax
    AMT
    Other Taxes
Business Taxes
    Business Income Tax Rates
    Depreciation
    Other
Macroeconomic Assumptions

Or (much more complicated) one could have these grouping expand on the main screen (e.g. you scroll down from the top to the Individual Tax Section and you see "+Regular Tax" - if you click the "+" it'll then expand and allow you to adjust the default values.

Agree with the primary point and that the expandable version would be even cooler if it isn't too hard.

I suggest putting the IIT params beneath the BT params in the list, though.

[MattHJensen]

@jdebacker, what do you think about prioritizing the reform file upload capability to allow taxcalc reforms on CCC over the field-based gui approach described in this issue?

I envision this being implemented by adding a new section to CCC nav called something like "IIT/FICA Reform File" in between "other" and "Macroeconomic Assumptions". The content of the section would look like this: Except "Reform File" would be replaced with "IIT/FICA Reform File" and the "See examples here" would come beneath the section title and we'd also include a link to TC/TD documentation.

Here's why I'm making this suggestion:

• Detailed reforms such as the Ryan/Brady blueprint and the Trump tax plan are immediately relevant, and these could be specified using the json reform upload capability but not using the field based gui we are envisioning.
• I imagine we could get the json reform file upload capability online faster than a nice form-based gui, although @talumbau and @PeterDSteinberg probably have a better sense of whether that is true than I do.

[jdebacker]

@MattHJensen, Seems ok to me. Has the file upload been getting lots of use on TB? I'm not sure how easy this is for most people so I was supposing it was more of an "advanced user" feature. If you think those users are the most relevant audience in the short run then, yes, I'd agree that allowing this first would be a good move.

[MattHJensen]

I'm not sure how easy this is for most people so I was supposing it was more of an "advanced user" feature.

Let's call it an "advanced user" or "assisted user" feature. Here's what I mean by assisted: the TC team can post the reform file for different high profile proposals at the examples page, and then all someone has to do is upload that file and tinker on the margins at will.

We've found this feature to be helpful for policy-maker users with extremely detailed proposals, and it is helpful when proposals are moving quickly or are time sensitive for other reasons, and we want to get new tax-calculator features onto the webapp quickly.

[MattHJensen]

Earlier I suggested that we pursue the json form upload before the gui approach based largely on the fact that:

Detailed reforms such as the Ryan/Brady blueprint and the Trump tax plan are immediately relevant, and these could be specified using the json reform upload capability but not using the field based GUI we are envisioning.

However, #436 will mean that all important outstanding reforms are available from the TaxBrain GUI, and https://github.com/open-source-economics/Tax-Calculator/pull/1109 will make it so that new reforms can be added quickly to the GUI.

Therefore, my new recommendation for this issue (#357) is to start off by making IIT and FICA parameters available on the CCC GUI rather than starting with the JSON upload.

In order to facilitate this approach, I reorganized the milestones by slimming down b2 and b3 so that #436 can go in b2 and #357 can go in b3 without slowing down progress on #357.

[jdebacker]

Given that that changes to pass-through business taxation are a large part of the tax reform discussion now, I wanted to re-up this issue. Even having just some preset IIT reforms to select would be very helpful.

cc @MattHJensen