That’s interesting.
I would add...if you are a Spanish Senator...your monthly salary amounts to 3,204 Euro, and some extra ‘bonus’ money if you hold privileged positions (ranging from 500 to 5100 Euro a month). Speaker of the Senate for example makes 5,117 Euro a month extra.
If you ask me...the PM is a worthless job...probably averaging 60 man-hours a week, and other than free coffee/drinks...it seems to be fairly bribable.