300 million Americans this month!

Sometime around the middle of this month, the U.S. Census Bureau clock will ring in the 300 millionth American.

The clock is an estimate based on an algorithm that takes into account births, deaths and immigration. The bureau collects monthly birth and death numbers from the National Center for Health Statistics, Bernstein said. Net immigration is derived from the American Community Survey, an annual polling of several million U.S. residents.
The Census Bureau hasn't forecast the day the milestone will occur, but the algorithm points to Oct. 16.

More details in the Los Angeles Times.