Changes in positions of CEOs of listed companies

In recent years intensified the changes in positions of CEOs of listed companies with a state share. In the 2016 7 year it was unchanged. In the 2017 year changes occurred as president in companies Pulawy SA, Energa SA (WIG20), JWS SA (WIG20) PZU SA Warsaw Stock Exchange (WIG20). The longest persisting remain as President of PKO BP from 2009 ri Alior Bank SA from 2008 year. Frequent changes clearly do not pursue the strategy of companies.
Minority shareholders must take into account the fact that do not affect the change