[npollock]

Would be great to see the language/framework also expressed as percentages of total posts over a period. Clearly there's a growth trend in job postings, would be nice to see the relative change in demand for each language/framework.

[IgorPartola]

Sort of, but if you are looking for a job and you are an expert at building web apps using C and MS SQL, then you don't care that it's an odd combination. You only care whether the number of openings is zero or non-zero.