My team is currently developing a service for use by the Indie game industry as well as the small and medium-sized development houses. We're going to try and seek some funds to help us out, so I'm writing a business case describing the market and how our service will be of benefit to the aforementioned customers. However, I cannot find any recent statistics (post 2005) on the estimated size of the actual indie (and small house) development industry to back up my figures.

Certainly with the advent of the recent mobile game market explosion with iTunes et al any figures more than 2 years old are going to be grossly inaccurate. I am a member of the IGDA was going to post a question on their forum (as I can't see any relevant text on their site, even in the annual reports), but I thought I would try here as a solid first stop.

I appreciate that this is a difficult question as I'm sure a lot of the indie developers (who have yet to release anything) are not going to be listed in any official charts, but I'd imagine that someone must come up with some figure on this.

Does anyone know where I should look for this information, or better yet does someone already have it?

Thanking you for your time

-Jason

As you can probably tell from the lack of replies you are going to have a hard time for a couple of reasons.
1. Meaningful sales data takes time and effort to compile. Companies only do this if they believe there is a market to sell such data. While big publishers will pay for data on mainstream games small indie developers don't have the budget (and big publishers don't have the interest) to make the sale of indie sales data worthwhile. Thus there isn't much formal collection of data. Some indies do release their sales data but this tends to be spread around on various different blogs and won't really give you an idea of the whole market.

You could try searching sites like http://forums.indiegamer.com/ and http://www.indiegames.com/blog/. The former is a forum where indies hang out and some post numbers. The later is an indie focused site that may have done some number compiling articles.

2. "Indie" is a sprawling an ill defined market. It covers everything from Xbox Live Indie Games to PSP Go, PC downloadable, browser games, flash games and Wiiware. There are also a whole range of companies from one person teams to big independent studios that can all claim to be indie.