When the nation's population hit the 100 million mark in 1915, the Model T Ford was a must-have item and silent movies were the rage.

Color television was groovy in 1967 when the population hit 200 million.

Today, it's all about iPods and "American Idol," and the nation's population is about to hit 300 million. The U.S. population clock, online at www.census.gov, was at 299,965,099 Thursday afternoon, and counting.

The U.S. Census Bureau projects the 300 million population landmark will be reached Tuesday at 5:46 a.m., based on an estimate the nation will add one person every 11 seconds.

That estimate is based on the expectation there will be one birth every seven seconds, and one death every 13 seconds. And net international migration is expected to add one person every 31 seconds.

The population growth is, in part, driven by immigration, which is also adding diversity. One in three Americans is now a minority, according to census estimates. And there are an estimated 34.3 million foreign-born individuals living in the United States, comprising 12 percent of the population. That's up from 13.5 million in 1915 and 9.7 million in 1967.

Mexico is the leading country of origin. In 1967, the bulk of the nation's immigrants were from Italy, and in 1915 most were from Germany.

Utah is also increasingly diverse — religiously, culturally and ethnically. That growth is driven largely by the Hispanic population, which boomed by 138 percent between 1990 and 2000.

"The very nature of immigration to Utah has changed over the last 100 years," said Robert Spendlove, manager of demographic and economic analysis for the Governor's Office of Planning and Budget.

Before 1950, most of Utah's immigrants were converts to The Church of Jesus Christ of Latter-day Saints, Spendlove said. Since then, the economy has become more of a driving force.

While Utah's natural increase continues to outpace the nation's, migration now accounts for about half the state's population growth, Spendlove said. Last year, migrants accounted for 41,000 of 78,000 new Utahns, according to estimates by the Utah Population Estimates Committee.

"The the highest level of migration we've ever seen," Spendlove said. "The result of this is our state is becoming much more ethnically and religiously diverse."

In 1910, nearly 80 percent of Utah's foreign born population was composed of mostly Northern and Western Europeans, said Pamela Perlich, senior research economist at the University of Utah. By 2000, the driving regions had shifted to Latin America — largely Mexico — and Asia.