I agree with what you're getting at, but stats like that will be somewhat skewed by the quality of managers coming in. The non-British inners of the Premier League are Pep Guardiola, Jurgen Klopp, Antonio Conte, Claudio Ranieri, Jose Mourinho, Manuel Pellegrini, Roberto Mancini, Carlo Ancelotti and Arsene Wenger. We're hardly shopping in the same market