Here is the trend for the proportion of people who say they pay attention to public affairs. The lower line shows the trend separately for younger adults, ages 18-25.

I notice a few points:

• It seems that “the Sixties” grabbed people’s attention–older people’s more than young adults’.
• The interest of the whole population has been pretty stable since the 1970s, despite momentous changes in the news media, which morphed from three TV channels and metropolitan daily newspapers to cable, the Internet, and cell phone apps. Even as the supply shifted, demand was steady.
• Younger people have been less engaged in recent years than in the 1970s, 1980s, and early 1990s.
• The past decade saw an upward trend for both age groups, albeit from low baselines.
• Young adults are not too far below their 1960-2008 average (about five points below), but the gap by age was larger from 1998 to 2008 than it was earlier.

All of this matters because people who pay attention have the most impact, and because habits of news consumption that form in early adulthood tend to stick.