What percent of Americans live to be 90 years old?

The total population of the U.S. in 2010 was approximately 308,000,000 and the approximate population 90 years or older was 1.9 million. Anyone who understands how to calculate percentage will find that the percentage of the population over 90 was approximately 0.62%, less than 1% of the population.

More information can be found in the Nov 2011 report at http://www.census.gov/prod/2011pubs/acs-17.pdf where a graph on page 3 unfortunately led someone else to report that the percentage of the population 90 and above was 2%. However, this figure is only associated with one aspect of the graph, which is a line representing the percentage of those 90 and above out of the population that is 65 and above with a corresponding percentage scale on the right side of the graph. The report actually never gives a percentage number that would answer this question.

The 1.9 million Americans of age 90 or above in 2010 were born at a time when the total population of the US was 106,000,000 or less (per the 1920 census). Ignoring any possible effects caused by immigration and emigration, we can say that approximately 1.8% of these people were still alive in 2010. No doubt this would have been slightly higher were it not for the approximately 450,000 US casualties in World War II and the Korean War, many of whom fell into this age cohort.

The percentage of Americans alive today who will live to see 90 is almost certainly much higher than the 1.8% of people born in the early 20th century who lived to that age (i.e. the current population of 90+ citizens), due to vastly improved healthcare, higher average living standards, and perhaps healthier behaviour as well (e.g. the decline of smoking). The answer to the question is a moving target, and we can't say for sure how many people born in any given era will live to 90 until it actually happens.