Percent of "yes"-replies to 22c: "In the last five years, have you taken part in a protest or demonstration about an environmental issue?".

In Environment III (2010) - question 22c.
In Environment II (2000) - question 21c.
In Environment I (1993) - question 21c.

A higher score means that more people participated in environmental protests in the 5 years prior to the survey. A lower score means that fewer people participated in environmental protests in the 5 years prior to the survey.