$28.[$FILE$]$ Consumption. The consumption function, first developed by John Maynard Keynes, captures one of the key relationships in economics. It expresses consumption as a function of disposable income, where disposable income is income after taxes. The accompanying table shows a portion of quarterly data for average U$.$S$.$ annual consumption $($in $$)$ and disposable income $($in $$)$ for the years $2000-2016.$

$\backslash$table$[[$Date$,$Consumption,Income$],[$Q$1,2000,28634,31192],[$Q$2,2000,28837,31438],[vdots,$vdots,vdots