One mini-waffle per country: each square is 1% of its population living in a city.
grid layout in split mode:
plotOptions.unit.grid.split: true draws one waffle per category,
grid.total: 100 gives each tile 100 cells and
grid.max: 100 fills value-of-100 of them, so every tile reads as
a percentage against its faint trackColor backdrop. Switching
the year is a plain chart.updateSeries(); each tile keeps its
cells in place and only the fill boundary moves. The unit / waffle chart is a
premium type; without a license it renders with a trial watermark.