For the fifth year in a row, U.S. employers have seen an increase in the number of wage-and-hour lawsuits filed against them in federal court, according to calculations by the Federal Judicial Center.

Plaintiffs brought 7,764 suits between April 1, 2012, and March 31, 2013, about a 10 percent jump since 2012, as illustrated in a graphic published by Seyfarth Shaw.

While it may be a record year for the litigation that involves disputes over the amount of pay that is owed to an employee, labor and employment lawyers say the figure represents part of a continuing trend.