Motorcycle helmet use has dropped in Michigan to 73 percent since a change in the helmet law last year, according to a survey by the Wayne State University Transportation Group. That's down from 99.4 percent in 2006. Michigan ended mandatory universal helmet use in 2012, letting riders opt out under certain circumstances. The drop in helmet use in Michigan is starting to show up in accident statistics, the researchers said. There were 109 deaths in 2011 and 129 in 2012. "As preliminary crash statistics from the 2012 riding season show significant increases in fatal and serious injuries, it appears that changes to the helmet use legislation has resulted in more severe injury outcomes," they wrote. "Based upon these findings, continued efforts are warranted to encourage the use of both motorcycle helmets and high-visibility gear."

http://detroit.cbslocal.com/2013/12/16/motorcycle-helmet-use-down-to-73-more-women-still-wearing-helmets/
http://www.freep.com/apps/pbcs.dll/article?AID=2013312160098
http://www.detroitnews.com/article/20131216/POLITICS02/312160062/-1/rss23
http://www.mlive.com/news/index.ssf/2013/12/number_of_motorcyclists_wearin.html
http://abc10up.com/michigan-motorcycle-helmet-use-drops/
http://fox17online.com/2013/12/16/michigan-motorcycle-helmet-use-drops-to-73-percent/#axzz2njf7oFM6
http://ca.news.yahoo.com/survey-helmet-michigan-motorcyclists-falls-73-per-cent-203233348.html