The 18th census in 1960 profiled a nation on the verge of the space age . � � There were more than 179 million people in U.S. , including the new states of Alaska and Hawaii . � � On the list of 10 largest cities , Los Angeles ranked number three , with a population of just under 2.5 million . � � In the decade to follow , U.S. Marines arrived in Vietnam , the Beatles appeared on American television , and 450,000 people jammed the Woodstock music festival . � � At the decade 's end , astronauts Neil Armstrong and Buzz Aldrin of Apollo 11 become the first humans to walk the surface of the moon . � � Profile America is in its 13th year as a public service of the U.S. Census Bureau .