%of u. s. citizens live in coastal counties, thus vulnerable to rises in sea level.

Approximately fifty-three percent of U.S. citizens live in coastal counties, thus vulnerable to rises in sea level.
Almost 124 million people or thirty-nine percent of the nation's population lived in counties directly on the shoreline. 123.3 million people or thirty-nine percent of the nation's population lived in counties directly on the shoreline in 2010.