Plot stacked missing and non-missing values over time (or some other discrete variable)

plotmissing.ado

// Plot stacked missing and non-missing values over time (or some other discrete variable)
// Syntax: plotmissing var timevar
program define plotmissing
  tempvar has hasnt
  gen `has' = (!mi(`1'))
  gen `hasnt' = (mi(`1'))
  graph hbar (sum) `has' `hasnt', ///
    over(`2', label(labsize(vsmall))) ///
    stack legend(order(1 "Non-missing" 2 "Missing")) ///
    subtitle(Relative frequency of non-missing '`1'')
end