As a nation obsessed with staying young it’s easy to forget the sacrifices of previous generations, particularly veterans including Baby Boomers approaching 50 and seniors 65 and older who fought in World War II, Korea and Vietnam.

The longevity of senior citizens continues to climb and their percentage of the population will continue to grow, according to government researchers, who say that by 2020 about 20 percent of the U.S. population will be 65 and older. In 2000, the nation’s senior citizen population was about 16 percent and that figure is expected to reach 24 percent in less than 10 years around 2020.

The federal government’s Administration on Aging (AOA) also says that the older population is becoming more racially and ethnically diverse as the overall minority population grows and lives longer. Hispanic seniors will also comprise a higher percentage of the estimated 38 million seniors today.

Advances in medicine and health care and a health-conscious and physically active generation of seniors have produced a large population of 80+-year-old Americans. Those born in the late 1920s and who grew up in the mid-1940s under President Franklin D. Roosevelt include around two million living veterans of the 16 million who served in World War II.

After retuning from war, many of these veterans, like Gilbert Lopez, never finished high school because of work, marriage and raising families.

Lopez, 87, is a father of eight children and was a member of this year’s spring 2012 graduating class at Wheat Ridge High School. He left school early and was drafted into the U.S. Navy in World War II as a teenager. This year he received his high school diploma under “Operation Recognition,” a program authorizing school districts to grant a high school diploma to any honorably discharged veteran who served in the United States military during World War II, the Korean Conflict or Vietnam War.

Lopez lost both his parents when he was 12-years-old and was drafted at 18 by the Navy in 1942. As a young adult Lopez served his country with distinction on board an aircraft carrier during the Pacific war with Japan. On Oct. 30, 1944 the USS aircraft carrier Belleau Wood was struck by a Japanese Kamikaze plane on her rear flight deck and the resulting fires and ammunition explosions killed 92 of the crew. Lopez earned 10 bronze stars for bravery, heroism or meritorious service aboard the Belleau Wood, which had a crew of 1,461 men.

At the spring graduation ceremony Wheat Ridge High School Principal Griff Wirth introduced Lopez to the crowd with brief remarks citing his military service and circumstances.

“This is a small, overdue, gesture,” Wirth said, “of our society’s gratitude for the sacrifice these individuals made.”

Operation Recognition is authorized by Colorado State Law and is granted by the Colorado Board of Veterans Affairs in cooperation with the Colorado Department of Education and the Colorado Association of School Boards. Thanks to the program, thousands of senior citizen veterans around the country are awarded high school diplomas and walk with their much younger peers.

“I’m very grateful and proud to have served in World War II,” Lopez said after receiving his diploma. And so were the faculty, staff and teenaged fellow graduates who gave him a standing ovation.