Luis Téllez walks into a white-carpeted room with lofted ceiling on the top floor of Mexico’s stock exchange (BMV), pulls up his beige corduroys to sit down, and in the process reveals a pair of electric pink socks.
It is Friday, and Fridays are now dress-down days, explains Mr Téllez. “This is something we’ve been doing since I arrived, and it seems to be working quite well,” says the tieless Mr Téllez as he adjusts the sleeve of his purple pullover.

