Where did you get the 15-30 million number? We believe the number is closer to 9 million.
For the United States, there are 1,336,300 programmers, according to the Bureau of Labor Statistics.
The United Kingdom has 333,000 "software professionals," according to the Office for National Statistics.
In Canada there are 387,000 people working in IT according to Statistics Canada.
I haven't dug down to other countries but it's unlikely you could get to 15-30 million. Most development tool vendors report that about 40% of their sales are in the US.
I did something similar to you pick up numbers from individual countries and summing them, I don't have the underlying data to hand (I did this about a year ago). But I'll do it again as I need the data anyway and post an update.
IDC put the figure at around 12million in 2002, and at 15million in 2008 though. I assume they did a more thorough job than either of us :-)
> Most development tool vendors report that about 40% of their sales are in the US.
I'm a programmer (living in Peru) and I have never spent a dime on development tools. I use emacs, kubuntu and friends. I also wrote (with friends) the site http://shapado.com which is an open source version of stackoverflow by the way :)
FYI, the world's population is about 22x the population of the US, so 15M doesn't seem crazy. That tool sales are lower in China does not necessarily mean that there are fewer programmers.
I wonder what would happen if you changed your measure from "professional programmers" to "professionals who spend a significant amount of time programming". I know where I work a minority of the people who have to write some code to get their job done have "programmer" or something similar in their title.
Also those who are registered as software professionals with the British Computer Society or similar are least likely to be using SO - either because they know all the answers - or more likely - are too busy doing flow charts of what their perfect system would look like if they ever actually did any programming.
For the United States, there are 1,336,300 programmers, according to the Bureau of Labor Statistics.
The United Kingdom has 333,000 "software professionals," according to the Office for National Statistics.
In Canada there are 387,000 people working in IT according to Statistics Canada.
I haven't dug down to other countries but it's unlikely you could get to 15-30 million. Most development tool vendors report that about 40% of their sales are in the US.