you would have better luck trying finding a US $4 bill.    for certain qualified income there is a 20% Qualified Business I Deduction.    generally applies to trade or business income (including real estate rental which has certain additional rules that must be followed) not wages or investment income also applies to income from publicly traded partnerships and certain REIT dividends.      it's a deduction not a credit. 

and there is a phaseout depending on filing status and taxable income.