Levene enrolled at Columbia University and in his spare time conducted biochemical research, publishing papers on the chemical structure of sugars. In 1896 he was appointed as an Associate in the Pathological Institute of the New York State Hospitals, but he had to take time off to recuperate from tuberculosis.
This graph shows the median age of the resident population of the United States from 1960 to 2015. In 2015, the median age of the United States population was approximately 37.7 years.
The population was spread out with 183 people (11.2%) under the age of 18, 74 people (4.5%) aged 18 to 24, 263 people (16.2%) aged 25 to 44, 597 people (36.7%) aged 45 to 64, and 510 people (31.3%) who were 65 years of age or older. The median age was 56.9 years. For every 100 females there were 91.4 males.