From: Impact of environmental and social attitudes, and family concerns on willingness to pay for improved air quality: a contingent valuation application in Mexico City
Bids in 2008 US dollarsa
7.5
12.5
25
37.5
50
57.5
62.5
75
87.5
Respondents
180
165
145
146
192
175
188
179
171
%no-responses
10.5
4.9
0.0
15.0
15.7
20.0
17.6
23.5
31.6