Older and increases in Hispanic population: People were living longer and the Greatest Generation and then the Baby Boomers began to retire. Immigration created a larger population of Hispanics in the US.
The Hispanic population increased greatly due to immigration. As a group they are now about 20% of the population making them the largest minority group in the US. The population has also become older with the younger generations numbering lower than the Baby Boomers and older. Life expectancy is also causing people to remain in the elderly bracket for longer than any time in US history.