A negataive number in the "difference" in rank column typically means the team had a good season and it's overall draft slot has declined. A positive number means the team had a poor season and the draft slot improved. A team like the Cubs, which didn't participate in Season 33 moved up 3 spots in the draft order just because the three teams (Mets, Indians, Cardinals) that were ahead of them all moved down (due to good seasons).