Turbo tax is subtracting self-employment tax deduction from my business income in order to determine my Qualified business income. What IRS doc says to do this?
Example results of turbo tax software:
QBI deduction: $3,944
From the 1040 instructions, page 34, "Determining Your Qualified Business Income": "It also includes other deductions attributable to the trade or business including, but not limited to, deductible tax on self-employment income"