Our World In Data visualises the empirical evidence of how living standards in the world have changed over the last decades, centuries, and millennia. Covering all of these aspects in one resource makes it possible to understand how the observed long-run trends are interlinked.
It’s a work in progress by Max Roser, an economist working at the University of Oxford. For each topic the quality of the data is discussed and the website also acts as a database of databases.
There are some revealing visualisations for Africa which show just how much progress or change the continent has experienced in a relatively small amount of time:
Annual GDP growth rate
Population density in Africa (1950, 2014 - 2100)
Daily food supply in Africa (1961 - 2009)
Literacy rate in Africa by generation
Mean years of schooling in Africa (1950 - 2010)
Child mortality in Africa (1990 - 2012)
Political regimes in Africa (1985 - 2012)