Add Sharing

I have setup ad sharing to only display on the bottoms of pages and posts and added my ad content. I setup it for a 50/50 split. No blogs have advertising setup yet.

When refreshing pages and posts, I am only seeing ads appear every other time. I thought that if the blog was not sharing (no ads on the blogs setup) that the adds would be shown 100% of the time. What did I setup incorrectly?