Gov. Chris Christie is nothing if not bold for taking on unions in the Garden State, considering how many union members there are in New Jersey. In 2009, 19.3 percent of the workforce belonged to unions, for a total of 721,012 members, according to Unionstats.com. The online database — compiled by professors Barry T. Hirsch and David A Macpherson of Georgia State University and Trinity University — indicates that there were 391,636 members of public employee unions, or 64.6 percent of government workers. The private construction industry has the next-largest group of union members, at 41,155 or 25.9 percent of that workforce. Overall, there are 329,636 union members in private industry. By percentage, New Jersey is number five in the country in terms of union membership. It now exceeds Michigan’s 710,024 workers, which make up 18.8 percent of the state’s total workforce.