Independent developer Jake Birkett analyzed how the revenues of the game for the first week and for the first year of sales on Steam correlate. He interviewed 30 developers and gave their answers in the form of a graph.
Birkett clarifies that in his research he considers a relatively successful game of the average indie developer, and asks not to take into account the income of AAA games of large studios.
According to the collected statistics, the amount of income of the first week by the end of the first year of sales grew in the range from 2 to 12 times.
Chart of revenue growth from first-year sales to first-week sales, by Jake Birkett
From these data, Birkett deduced an average coefficient of 5.1. After calculating the revenue for the first week, the creator of the game can multiply this number by 5.1 and find out how much he can expect in a year.
The coefficient can be increased in a lot of ways by stimulating sales through advertising, promotion through streamers, release of updates, DLC, and so on. The game can get good reviews from players and the press, which will also have a positive effect on its monetization.
Jake Birkett warns that his theory is not suitable for accurate forecasts of profitability and gives a very rough idea of future revenue.
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