Figure 3

Comparison of temporal changes of diversity (\(N_{\mathrm{H}}\)) in the set of 61 cites. The coordinates of dots are the pairs (city, its diversity). Abscissas of the dots identify a city by their 1990 diversity ordering from the smallest to the largest. Ordinates of the dots are the diversity values in a year as indicated by the dots’ colors. Names are shown only for 29 selected cities to avoid overlapping. Two color bars link cities to the regions in which they are located. The upper bar corresponds to the 1990 ordering (in agreement with the x-axis), while the lower bar corresponds to the 2020 ordering