Tesla shares fall and a big loss for Elon Musk .
Tesla's stock fell back strongly, falling around 9% The share price fell from 238.7 dollars to 217.8 dollars .
While Elon Musk, the richest man in the world, lost about 15 billion dollars .
That big decline of the company comes due to Tesla car models
Cybercap and robovan that did not impress investors .
