Let’s say we’ve managed to find an interesting dataset 1 on heights for given countries since 1550 (yup!): country year height_cm continent Afghanistan 1870 168.40 Asia Afghanistan 1880 165.69 Asia Afghanistan 1930 166.80 Asia Afghanistan 1990 167.10 Asia Afghanistan 2000 161.40 Asia Albania 1880 170.10 Europe We’ve got country, year, height (in centimetres), and …