Find out their monthly burn rate and divide by 600MM So, in may 2008 they were said to burn 150MM / year. Lets assume thats doubled - so, 300 MM per year. 30

Find out their monthly burn rate and divide by 600MM So, in may 2008 they were said to burn 150MM / year. Lets assume thats doubled - so, 300 MM per year. 300/12 = 25MM per month 25/600 = .04 cents per month, per user.