Its a little more complex than that.
You need to know when the software was sold relative to the purchase date of the console.
What you would expect is more software nearer the original purchase of the console pattering out later in life
It might not work that way. The point of manipulating data is to remove bias, and make conclusions based on the data.
Making conclusions you suggest requires more and different data. I dont know if the OP has enough data in order to figure out whether the sale of software is at it's peak when it is sold and then decreases with the life time of the purchase.