The world has changed a lot in the last century, with ever-developing technologies creating new careers, while rendering others redundant. However, there are some jobs that are as crucial now as they were all those years ago. But how have the salaries they pay changed? Click or scroll through 20 of America's oldest jobs to discover how salaries in 1921 compare to today, with historical figures calculated to reflect inflation. Historical data is taken from the Bureau of Labor Statistics’ Union Scale of Wages and Hours of Labor report, while modern salary data is taken from Glassdoor.