Supplementary Table 1. Forecasts 2020 - 2030 for GSS moral issues.; Supplementary Table 2. Examples of moral arguments.; Supplementary Table 3. Forecasts 2021 for GSS moral issues.; Supplementary Figure 1. Excerpt of the argument questionnaire.; Supplementary Figure 2. Historical trends and forecasts for 2020 - 2030. from Predicting how the U.S. public opinion on moral issues will change from 2018 to 2020 and beyond

Forecasts with 50% prediction intervals for 2020 to 2030 for GSS items (on moral issues) that were asked within the last 10 years.;Kinds of moral arguments, with three generic examples of each. ;Forecasts with 50% prediction intervals for 2021 for the 60 GSS items (on moral issues) that were asked in the 2021 GSS.;Excerpt of the questionnaire used to measure the argument advantage of moral opinions.;Historical trends (black) and forecasts (purple) for 2020 to 2030 with 50% prediction intervals in the popularity of 102 moral opinions in the United States.