Although slaves had been sold in the American colonies since at least 1619, slave labor did not come to represent a significant proportion of the labor force in any part of North America until the last quarter of the 17th century. After that time, the numbers of slaves grew exponentially.
A Pharmacologist earns an average salary of $103,686 per year. For the first five to ten years in this position, salary increases sharply, but any additional experience does not have a big effect on pay.
The average salary for a Clinical Research Coordinator is $47,914 per year. People in this job generally don't have more than 20 years' experience.