Not sure exactly how indicative these numbers are but:
SQL fell from 59.6% to 57.1% and then 48% (-11.6%).
C# from 44.7% to 37.6% and then to 31.6% (-13.1%).
C from 26.9% to 17.9% and then to 16.4% (-10.5%).
while at the same time
Node.js went from 7.5% to 9.8% and then 13.3% (+5.8%) and AngularJS from 0 in 2013 and 2014 to 13.3 this year.
If I wanted to sound smart I could say that it looks like database administration and systems engineering is declining while web development is on the rise. But I won't. It's worth noting, in any case, that the respondents were 8k in 2013, 6.5k last year and ~22k this year.