Uh oh, this is the can of worms I call the QS First Principle. Philip is more QS Last. (:
Basically, I hate protocols like “enter a 1 if there’s nothing to read”. The graph should always show you something interesting about the actual world, like how many posts you read!
In any case, what about just setting a goal value for the current total number of blog posts that have been published and periodically bump it up as it grows (and if you still want to keep reading it)?