I wanted to learn how the standard deduction is calculated. When i looked up statute 26USC63, it appears the deduction is simply an arbitrary amount with no mathematical basis. I would have thought, because the standard deduction substitutes for itemized deductions, that it represented some average deduction amount or similar. However, the law does not describe how or from where the standard deduction is derived. What makes things even more odd is that the standard deduction does not change with income. Whether you make $1K or $100K, it is the same. Is there another information source that details what is behind the standard deduction, or is 26USC66 it?
26USC66
(c) Standard deduction
(2) Basic standard deduction
For purposes of paragraph (1), the basic standard deduction is—
(A) 200 percent of the dollar amount in effect under subparagraph (C) for the taxable year in the case of—
(i) a joint return, or
(ii) a surviving spouse (as defined in section 2 (a)),
(B) $4,400 in the case of a head of household (as defined in section 2 (b)), or
(C) $3,000 in any other case.

