Fig. 4

Evolution of graphical displays for meta-analytic data over time, differentiated by graph category. For each year, the cumulative number of available graphical displays for meta-analytic data is shown. The composition of available graphs is shown by colored areas, according to the specific category within the taxonomy of graphs. Of the total of 208 ascertained plots, only those 156 plots with retrievable year of introduction (see Table 3) are shown. The four categories containing the fewest graphs are merged to “other categories”