Characteristics of Recent S&E Graduates: 2003 [nsf06329]
Statistical Reports on U.S. Science
Median salary for a person with an MS degree in ECE: $70k
With a BS degree in ECE: $53k
A MS degree resulted in a 32% jump in salary.
MS in ME: $65k
BS in ME: $50k
A MS degree resulted in a 30% jump in salary.
MS in CS and IS: $60k
BS in CS and IS: $45k
A MS degree resulted in a 33% jump in salary.
Thus, I think it is fair to say that a MS degree results in a 1/3rd increase in median salary, for any major.
From Table 29:
Of the 112k sampled, in engineering:
35k want an MS in ECE (30%)
25k want an MS in ME (22%)
Of the 682k sampled in science
85k want an MS in Computer and Information Science (12%)
Note: the MS degree with the higher median salary is more sought after.