Beschreibung:
Temporal aspects of environmental preferences and willingness to pay (WTP) have not yet received attention comparable to their importance. We investigate how WTP and preferences have evolved over five years. Data generated by two identical contingent valuation surveys on oil spill prevention applied to a high-quality internet panel of Norwegian households in 2015 and 2020 were analyzed. The 2020 respondents consisted of both new and a number of retest participants. This data structure is rare in the literature, and our test-retest (TR) sample is the largest of any studies beyond 1-2 years. We find a significant increase in WTP when comparing full samples of all individuals, while no significant change is found in the TR sample. Estimated preference functions are stable for both samples when controlling for various factors. Utilizing decomposition analysis, we find that a negative shift in preferences causes WTP to decrease among TR respondents. Using COVID-specific survey questions and matching the number of COVID cases in respondents' county on the day they completed the survey, we find that the pandemic likely produced a downward bias of 10-20 percent on WTP in 2020. Further investigations suggest this is due to psychological, rather than economic, implications of the pandemic