Jay Paroline

I’m probably not at liberty to speak about specific numbers, but I have to share my elation at Grooveshark’s current growth rate.
Last month I predicted that given our current growth rate, we should double our total number of users every 3.6 months.

We are one day away from hitting a big round number, so I thought I’d look back and see how long ago we were at half of that. What do you know, 3.5 months ago. A growth rate slightly better than I had projected.

This, my friends, is exponential growth, and it turns out that when you have exponential growth it is insanely easy to calculate how long it will take to double your numbers. It’s called the rule of 72 and it basically states that you simply divide 72 by your growth rate to get your doubling time. For example, 72/(20% per month) = 3.6 months.

I must credit Dr. Albert Bartlett for teaching me about the rule of 72. According to Dr. Albert Bartlett, “the greatest shortcoming of the human race is our inability to understand the exponential function,” and I highly recommend watching his lecture on the topic. (sorry, it’s a .ram file. here is an alternate version on google video, which I haven’t watched)