The first graph is the population growth in Africa from the 1500s to the 1800s. There is a steady linear growth between the 16-1700s all increasing by about 10 million but from 15-1600s there looks like there was a small jump in population by about 12 million.
The second graph is the number of slaves exported. During the 16th century there was barely any slave exports, but by the 17th century the number grew exponentially and slave exports increased to about 20,000. From the 17th century to the 18th the number of slaves grew exponentially once again and it jumped to above 50,000 probably due to the increasing demand for slaves.
The third graph shows the destination of slaves. Half of them went to the Caribbean probably to work on Spanish plantations in very preferable plantation weather. More than a quarter then went to Brazil to Portuguese plantations in also preferable planting climates. Then the next most went to Central America and South America and the rest went to North America. There were probably more plantations already set up and worked for in the areas with more slaves and the north only used slaves to do domestic tasks and didn’t have many plantations for them to work on.
I think the population graph contradicts what the book says about African society. The book implies that many African males were taken and women had to take over their roles because there weren’t enough people yet the graph shows that African population was increasingly steadily throughout the slave trade period. The destination graph however was interesting because the book implies that Portugal and Spain bough many slaves to work on their plantations in the Americas, yet only a handful of slaves went there. Most of them went to the Caribbean and that is something that is barely explained in the book. The Spanish did have colonies there, but the ones in the Americas are mentioned more. The African slave export graph was supporting of what the book said about slave trade. As people found out about cheap labor the demand went up and more people were sold as slaves and shipped around the world, so that graph supports the book’s explanation of many saves being traded and circulated throughout the societies.