Highest salary at Phelps in year 2011 was $61,138. Number of employees at Phelps in year 2011 was 31. Average annual salary was $33,771 and median salary was $45,505. Phelps average salary is 28 percent lower than USA average and median salary is 5 percent higher than USA median salary. From 2010 to 2011, the average salary of employees at this employer increased 2.9 percent, the median salary increased 2.6 percent.