n_missing(..., type = c("any", "all"))

n_not_missing(..., type = c("any", "all"))

n_total(..., type = c("any", "all"))

if (require(NHANES) && require(mosaic) && require(dplyr)) {
  mosaic::tally( ~ is.na(Height) + is.na(Weight), data = NHANES, margins = TRUE)
  NHANES %>%
    summarise(
      mean.wt = mean(Weight, na.rm = TRUE),
      missing.Wt = n_missing(Weight),
      missing.WtAndHt = n_missing(Weight, Height, type = "all"),
      missing.WtOrHt = n_missing(Weight, Height, type = "any")
      )
    }