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Question: Creating a Numbers spreadsheet to calculate income tax

If you've a little time now and then it's good mental exercise and certainly useful to create a spreadsheet that will calculate your income tax or whatever tax you're paying. This frees you of having to erase errors from paper forms, and since post offices don't provide blanks anymore, that's a tremendous advantage. Over the past few tax seasons I've assembled such a spreadsheet, containing all the forms I use. I starting by writing a 1040 form and adding the A, B, D, E, 8949, and 6251 schedules. I've recently put in a couple of the worksheets found in the various instructions, and my spreadsheet is currently about 80 rows deep and AQ columns wide. Each of the forms contains all the rows I use, so the spreadsheet Is full of IF, AND, and OR functions and lots of adds and subtracts, but the whole thing takes up only about 700 KB of memory. Since all the forms are on the same spreadsheet, cell contents needing to appear in more than one cell instantly do so via cell references. I do end up typing the numbers into the interactive pdf forms and printing them, but that's no biggie after years of messing with an adding machine and pencils. So far, what I've created seems to work okay, since the IRS has not questioned my submissions other than a couple of rules interpretations.

MacBook, Mac OS X (10.4.11), null

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Mar 18, 2018 6:40 AM in response to Lemastre In response to Lemastre

You can purchase tax software for $35 dollars that handles this for you. The reason I mention this is that each year, potentially, congress can change the tax laws and you will have to keep up with such changes. I do not recommend trying to create your own forms unless you are willing to read the latest tax law and understand the implications to the various calculations.

Mar 18, 2018 6:40 AM

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Mar 18, 2018 11:52 AM in response to Wayne Contello In response to Wayne Contello

If you're interested only in producing completed income tax returns with the least input of time, buying commercial tax-prep software is probably for you. When I started my spreadsheet project, I'd hoped to create a spreadsheet that would shorten time spent in future years without costing the money. But now the project is mostly about seeing how well I can actually do it. I'm not a very efficient programmer, and if I didn't have the time required, I probably would have dropped the project by now. Regarding Mr Contello's assertion about understanding the tax code, I doubt that we really need to understand it. I've not met anyone who even claims to have done that (I understand it's about 2,600 pages long in its purest form http://tinyurl.com/m6tv6dh). What a tax-preparer and the software he uses need to understand is what's written on the tax forms and in their instructions. I assume these instructions convey what the tax code intends for us to do, and I'm fairly sure it's what the IRS looks for when it scans our returns.

Mar 18, 2018 11:52 AM

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Question: Creating a Numbers spreadsheet to calculate income tax