The life expectancy for citizens of the U.S has decreased again and left many searching for answers. This is the third year in a row that such a decrease has occurred and should be a cause for concern. The data continues the longest sustained decline in expected life span at birth in a century, a performance not seen in the United States since 1915 through 1918. That four-year period included World War I and a flu pandemic that killed 675,000 people in the United States and perhaps 50 million worldwide.