Confidence in Banks. Since 1973, Gallup has asked Americans how much confidence they have in a variety of U.S. institutions.

One question asked of those polled is whether they have a great deal of confidence in banks. In 2007, of a random sample of 1008 adult Americans, 413 said yes; and, in 2013, of a random sample of 1529 adult Americans, 398 said yes. For the two years, find and interpret a 95% confidence interval for the difference between the percentages of adult Americans who had a great deal of confidence in banks.