The Center’s analysis pointed to two issues: partisan differences in willingness to join the ATP and in likelihood of dropping out of the panel. [...] In the rest of the country 11% of sampled households agreed to join the panel.5 In analysis controlling for local levels of wealth, education, and racial composition, the electoral support for Trump remains a negative predictor (albeit a modest one) of a household’s likelihood of joining the ATP.6 On balance, these analyses suggest that Trump supporters may be slightly less likely than others to j [...] Political party identification was not measured on Whatever the cause, the newer the panel in 2014, and so the figures for the 2014 cohort come from a survey fielded March 10 to April 6, 2015. [...] Panel recruitment The ATP was created in 2014, with the first cohort of panelists invited to join the panel at the end of a large, national, landline and cellphone random-digit-dial survey that was conducted in both English and Spanish. [...] If two or more adults were in the household, the letter asked the adult with the next birthday to complete the survey.