washington president donald trump repeatedly say propose tax cut would big u.s. history even come close record trump would target talk corporate tax include tax boast president fellow republicans congress propose cut top corporate tax rate 20 percent 35 percent succeed would large american corporate tax cut since modern corporate tax begin century ago propose republicans corporate rate would fall 43 percent compare second-largest cut 26 percent republican president ronald reagan 1980s individual tax trump 's claim hold accord data top personal income tax rat collect tax foundation washington think tank graphic track u.s. tax rat see tmsnrt.rs/2z5cv20 republicans congress back away cut top individual tax rate 39.6 percent even cut low trump want 35 percent president would even come close win brag right reagan cut low top rate 28 percent 70 percent impressive 60 percent drop huge tax cut president warren harding president calvin coolidge republicans take prize 1922 top tax rate 73 percent 1925 25 percent almost 66 percent decline coolidge alone responsible 57 percent cut tax president john kennedy president lyndon johnson democrats tax cut 1964 1965 cut top rate 70 percent 91 percent decline 23 percent still ways measure size tax cut besides rat one approach would measure much tax revenue federal government get taxpayers get keep cost tax cut number dispute favor tax cut trump administration argue tax cut ignite economy tax revenue increase decrease way cut pay say committee responsible federal budget bipartisan washington think tank estimate trump tax cut could fourth-largest percentage gross domestic product gdp measure national economic output think tank favor measure eliminate effect inflation economic growth size total federal revenue measure agree number economists say reagan cut large history even large coolidge brag right all-time big tax hike winner democratic president woodrow wilson world war one increase top individual rate 77 percent percent corporate rate 12 percent percent trump 's tax cut wo n't big u.s. history