Michael Avon of Canton-based global mobile ad company Millennial Media will be stepping down as CFO of the company in June.<br /><br />He had been in that position since 2009, and shepherded Millennial Media through its initial public offering in 2012.<br /><br />The news comes at the same time that Millennial Media’s shares dropped 40 percent. According to the Baltimore Sun:<br /><br />    Millennial lost $12.9 million on $72.6 million in sales in the three months ended March 31, compared with a $3.8 million loss on $49.4 million in sales in the same quarter of last year.