As of 2018, there were 52 million adults 65 and over in the United States. A recent Population Reference Bureau study predicts that number will nearly double by 2060 to 95 million aging adults, who will then comprise nearly 25% of the country's total population. Some states in the nation have faster-growing aging populations than others, as a new survey from AgingInPlace.org reveals. Using data from PRB and the U.S. Census Bureau, AginginPlace.org calculated not only the states with the fastest-growing population over 65, but also which states saw the largest percentage increases in that population since 2010. The study also took a broader look at the over-65 populations in each country in the Organisation for Economic Co-operation and Development (OECD) . Of those 30 countries in the OECD, Japan took the top spot, with 28.79 percent of people over age 65. At 84.7 years, Japan also has the highest life expectancy on the list. Italy follows in second place, with 23.37 percent of the population over 65, and is the European country with the largest population of elderly citizens. Finland is in the third spot, at 22.49 percent. The country's percentage of elderly was 17.26 percent in 2010, resulting in a 30.3 percent increase over ten years. The United States is in the 25th spot, at 16.89 percent. For U.S. states with the biggest growths in aged populations, Alaska comes in first, with a 70.13 percent increase over ten years. Even so, Alaska has the second-smallest over-65 population of the 50 states. Wyoming takes the second spot, with a 43.55 percent increase in ten years, although it ranks in 20th place for states with the largest elderly populations. New Hampshire ranks third for fastest-growing at 42.96 percent and is the highest-ranking state that also appears in the top 10 for highest proportion of people over 65. See our slideshow above for those top ten states, and click here for the full study.