Every time this comment is posted about non usa geographic area, somebody will post, but in US you have deductions, allowance, dividend, smaller profits, gifts.

Every time this comment is posted about non usa geographic area, somebody will post, but in US you have deductions, allowance, dividend, smaller profits, gifts. Which for sure all other countries too have, and somehow they have sorted this out. I think its the lobbying and the general mistrust of government "telling" a number vs calculating the number yourself. (Although if that is a wrong number, government/IRS tells the correct number).