The Spanish financial media Cinco Dias published an article that shows the trends in the wage gap between employees and executives over the last 4 decades both in the US and Spain. 

"In the Spanish market, a considerable compensation gap between top management and employees may be challenged by shareholders and result in a negative vote at AGMs for neglecting the social capital or impact the rating of ESG agencies, undermining investment decisions of some asset managers,” explains Borja Miranda, Head of M&A and Activism for Europe at Morrow Sodali.

Full article here (in Spanish only)