This article accompanies The Trouble with Retaliation.

According to the U.S. Equal Employment Opportunity Commission, retaliation claims were the most-often-filed charge by employees in fiscal 2011.

That charge surpassed racial-discrimination claims in fiscal 2009 -- and the margin has been growing ever since then.

Here are the EEOC's statistics on the number of discrimination claims filed from fiscal 1997 through 2001, including all types of claims, as well as some Facts About Retaliation, a document created by the EEOC to help employers better understand what constitutes retaliation -- including definitions and explanations of "adverse action," "covered individuals" and "protected activity."