Generic chart for a mirrored histogram

[DennisGoldfarb]

Like this but a histogram: https://www.d3-graph-gallery.com/graph/density_mirror.html
It should handle both categorical and numerical data. My thinking is that there are some charts where we'll have data for the patients in the draw region (e.g. age) and we'll have data from the region itself from census demographics. It would be nice to plot those in a mirror'ed form to quickly see if there's a bias.