what the hell is the air industry
Y'know, like that one businessman in the stuffty Lorax movie! He sells air!
Air has been trading at 0$ for millennia. That makes it one of the most stable options for your stock portfolio.
http://www.independent.co.uk/news/uk/home-news/man-sells-british-fresh-air-to-wealthy-chinese-elite-for-80-a-jar-a6857461.htmlprices have risen, folks!