As the average number of miles driven by Americans heads into its eighth year of decline, a new report from the U.S. Public Interest Research Group(PIRG) Education Fund finds that the slowdown in driving is likely to continue.

Baby Boomers are moving out of the phase in their life when they do the most commuting, while driving-averse millennials move into that phase. These demographic changes and other factors will likely keep driving down for decades, according to the report, “A New Direction: Our Changing Relationship with Driving and the Implications for America’s Future.”