Increases in lifespan in the US since the 1950s have been far more from bringing up the lower end (improved outcomes for underprivileged minorities) than by extending top-end (white female &amp; male) life expectency.  Almost as if there were a diminishing returns setting in.<p>There&#x27;s actually been some recent improvement following the 1990s, but the <i>vast bulk</i> of life-expectency &#x2F; mortality improvements came <i>prior</i> to 1920. Predating virtually all of modern medicine, but benefiting tremendously from antisceptics, sewerage systems, municipal garbage collection, refrigeration, and some early food safety and disease control, especially over cholera, tuberculosis, and yellow fever.