The input values might be derived from real-world measurements, such as keystrokes, mouse movements, or the contents of your hard drive.

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To see the effect of capping or eliminating itemized deductions, for example, you can start with one of the example taxpayers and reduce or zero out the input values for some or all of their deductions.

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To do this, you will need to monitor the value of your portfolio and the ETF on a daily basis and input the values into the green columns on the sheet.

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Generally, residents in the neighborhood get the opportunity for input, but if it is rezoned anyway, it could affect vacancies, rents and property values.

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