This seems based on GAO report ,released some time ago.
It gives median salaries between Citizens and H1Bs
across 2/3 age groups.(you can search the report under GAO)
Median salary it self denotes an average salary.
That too this GAO report has taken some of the groups and may not of community in it's entirity .
The quetsion may be is it bench mark? and who ever draws less than that is really bad?
No, since median deviates from actual above and below salaries
and the item is not true of in it's sense.