Scale of Tax

I have one old Scale of income-tax on MAS:
http://twt.mpei.ac.ru/mas/worksheets/MC_f_S_I_6_4.mcd
and I do know is it real or not.Pro week, month, year..
Can somebody send me any real actual Scale of income-tax in USA, UK etc (better as Mathcad-file)
We have now for example a fixed income-tax (13%) in Russia (for simplify of calculation only I think).
Val
http://twt.mpei.ac.ru/ochkov/v_ochkov.htm