Average reply to 8a: "How much do you feel you know about the causes of these sorts of environmental problems?". (1) Know nothing at all - (5) Know a great deal. Replies (8) Can't choose are deleted. "These sorts of environmental problems" refer to (1) Air pollution, (2) Chemicals and pesticides, (3) Water shortage, (4) Water pollution, (5) Nuclear waste, (6) Domestic waste disposal, (7) Climate change, (8) Genetically modified foods, (9) Using up our natural resources.

In Environment III (2010) - question 8a.
In Environment II (2000) - question not part of the survey.
In Environment I (1993) - question not part of the survey.

A higher score means that more people feel that they know about the causes of environmental problems. A lower score means that fewer people feel that they know about the causes of environmental problems.