Head Coach Retention Rates
The above url (link) is one of those articles that you wonder why no one has done it before and though it may not be a hot bed of a topic for discussion, it does merit discussion.
Though the rate seems to be about the same as in years past whether going with a 5yr or 3yr retention rate. Where everyone's focus is a winning correlation with head coach and staff retention. Those teams which have less turnover at their coaching positions seems to have a better winning percentage.
Now the article doesn't go that deeply into the general perception of winning = head coaches retention, just if they are still with the same team, so it would be nice to see this topic with a more in depth view.