Otto Neurath is generally noted as the man who developed a method of displaying numerical and statistical information through Isotypes, alongside his wife Marie, such that this information is more readily available to a greater audience and one that doesn’t rely greatly on literacy, in format that is learning without language.

The main method of doing this being minimalist pictures of people or an element that you wished to show scale or numerical density, these could be laid out in subsections to present how many of this item belonged to a particular classification, though colour can also be used though this can add complexity if there are too many classifications where more colours seem too similar.

Above shows the size of the armed forces across the world in 1930, after the defeat of the German Empire and the buildup to the second world war, each subsection a country or group of countries. With each full man equating to around 400,000 soldiers, to a total of 25 million soldiers.