Original: Since the first round of the NHL playoffs consist of 8 series (16 teams), there will always be 22 teams in this list - the 14 teams that don't make the post-season in the last season plus the 8 teams that lost the first round playoffs.
Simplified: Since the first round of the playoffs consists of 8 series (16 teams) and there are 30 teams in the NHL, there will always be 14 teams in this list.