A few months back Mike Roberts, the curator of IFDB, together with Andrew Plotkin released the full IFDB database dump. This is certainly a great deed, since the IFDB is the most complete source of information about IF to date and there's always a risk of data loss if the database is behind only one person. The database is an invaluable resource to (future) historians, researchers and people who love statistics.
And I do love statistics.
I've pulled a lot of interesting graphs from the database and will present them in a series of blog posts, of which this is the first one. We'll start slow by looking at the games' publishing dates and progress later to searching for more and more specific correlations.
It's worth noting that while IFDB has a lot of information, it's by no means comprehensive or 100% accurate. Therefore all this data reflects IFDB contents rather than the real world. How much the truth differs from the available data is open to discussion.
Click on the images to see the full data set, an interactive chart and chart display options. All available statistics can be seen collected on this page. More graphs are added as the series progresses.
You can also gladly suggest in the comments what kind of data you'd like to see analyzed.
Publishing date by year
There are 4173 games in the database, of which 4027 have a known publishing date. The graph for total number of games over time looks like this:
More informative is the number of games published each year:
You can see the "golden age" from mid-80s to early 90s, a small dip, and a steep rise starting soon after. I have no explanation for why there were so many releases in 2001–2003. In 2001 there were twice as many releases as in 2009.
In recent years the number of releases has varied between 115 (in 2009) and 173 (in 2010). There's no discernible trend to either direction and there's not enough data to make any predictions about the future. 2012 is not included in the graph but at the end of October there were 164 releases which is already more than in 2011 (153 releases).
This (and the next graph) is wildly inaccurate since about 70% of games have only the publishing year listed, not the exact date (which is why January 1st is excluded). Still, you see what you'd expect: IFComp games are released in October so it has the most releases and November is not a good time to release because the competition draws all the attention.
Games are released most often on Sunday and least often on Friday. Shouldn't be a surprise that weekends are the most common release days as most games are hobbyist efforts.
Next time we'll look at development system popularity.