While people can often estimate how much they might need for 10 or 15 years of retirement, that calculation becomes more difficult for retirement that could last 20 years or more. Gary Waters/Ikon Images/Getty Images hide caption

itoggle caption Gary Waters/Ikon Images/Getty Images

Phillip Underwood and Michelle Sheridan and their children, Logan and Lilliana, gather in their living room in Frederick, Md., after a long day of work and school. The couple had delayed marriage, in part for financial reasons. James Clark/NPR hide caption

itoggle caption James Clark/NPR

Outside a Taco Bell restaurant in Warren, Mich., early Thursday, supporters of the push by fast-food workers to raise the minimum wage were marching. Jessica J. Trevino /MCT/Landov hide caption

itoggle caption Jessica J. Trevino /MCT/Landov