Charles Booth, a successful British businessman, created a map in the late 1800s that showed levels of poverty in London. Booth believed official estimates underestimated poverty levels. His own research revealed that as many as one-third of Londoners lived in poverty, even worse than reported. Booth's map used color coding to represent varying degrees of poverty. His in-depth study took into account many social factors and helped reveal the true extent of poverty in London.