The index values are calculated as weighted shares of responses. Each answer of “increase significantly” is multiplied by a factor of 1, “increase slightly” by 0.5, “stay roughly the same” by 0, “decrease slightly” by −0.5, and “decrease significantly” by −1.

The index values thus span from +100 (if all participants answer “increase significantly”) to −100 (if all participants answer “decrease significantly”).

The index values are calculated as weighted shares of responses. Each answer of “extremely pressing problem" is multiplied by a factor of 1, “pressing problem” by 0.75, “average problem” by 0.5, “small problem” by 0.25, and “no problem at all” by 0.

The index values thus span from +100 (if all participants answer “extremely pressing problem”) to 0 (if all participants answer “no problem at all”).

The index values are calculated as weighted shares of responses. Each answer of “yes” is multiplied by a factor of 1 and “no” by 0.

The index values thus span from +100 (if all participants answer “yes”) to 0 (if all participants answer “no”).

The index values are calculated as weighted shares of responses. Each answer of “increased significantly” is multiplied by a factor of 1, “increased slightly” by 0.5, “stay roughly the same” by 0, “decreased slightly” by −0.5, and “decreased significantly” by −1.

The index values thus span from +100 (if all participants answer “increased significantly”) to −100 (if all participants answer “decreased significantly”).