Data was compiled by Our World in Data based on a number of historical sources. Data is based on best estimates: there is greater uncertainty in earlier historical data but is provided as the best estimate of the time.
Source: Rhino Resource CenterData was compiled by Our World in Data based on a number of historical sources. Data is based on best estimates: there is greater uncertainty in earlier historical data but is provided as the best estimate of the time.
Source: Rhino Resource Center