Statistics on wages in IT for the first half of 2019. Reliability of summary indicators: HOW and WHAT to check?

Question

Freelance

Salaries in IT in the first half of 2019: according to...
Who and how checks such statistical information for veracity? (or do you take everything for granted?)
Maybe there are other services that collect such data?
Thanks to.

Answer 1

0. ( link from the question )
1. Raz.
2. Two.
3. Three
Link from sim3x (in Ukraine):
jobs.dou.ua - https://github.com/devua/csv/tree/master/salaries

Answer 2

Anyone can check, it's made on the public data of my circle

Answer 3

What is Habr, what is Toaster, a club of millionaires.
There are specific vacancies, and focus on them.

Answer 4

look here and dream that it will also be like this sometime here,
when they begin to comply on both sides