Engineers, who were the leaders of the Underground Railroad, helped slaves who were running away by providing them with food, shelter, and sometimes jobs. They hid the slaves from people who were trying to catch them and return them to slavery.
The GDP per Capita, in Nigeria, when adjusted by Purchasing Power Parity is equivalent to 32 percent of the world's average.
About This Statistic. The statistic shows global GDP (gross domestic product) from 2010 to 2014, with projections up until 2020. In 2015, global GDP amounted to about 74.2 trillion U.S. dollars.