The Census Bureau’s new population estimates show how America has changed since 2000 and what it might look like in 2010. America is growing and aging, people and congressional seats are moving south and west, magnifying the importance of such issues as redistricting, entitlements and immigration reform.

If we assume that the states continue to grow at the rate they have since 2000, then by 2010 America will have grown by 10 percent, having added 29 million people, and will have more than 311 million people. From 1990 to 2000, we grew at an even faster clip, by almost 33 million people, or 13.2 percent.

But even if our growth has slowed, America’s increase in population is the envy of the developed world, where many countries are beginning to lose population. There were fewer Japanese in 2005 than 2004, the first year of a long projected decline. Italy and Germany have also begun their declines. Russia and Eastern Europe started losing population in the early 1990s, with Russia having lost 5 million people, or nearly 3 percent since its peak.

Developed countries will face severe challenges as their populations age, as their fewer workers are asked to support more retirees. Japan, for example, has a median age of nearly 43, almost seven years higher than the United States, and while we are aging our growth resulting from higher birth and immigration rates will mean that we face this demographic challenge later and less severely than other countries.

Growth in the United States is regional. The Northeast and Midwest states are our Europe, creeping along, barely growing or even shrinking. Since the 2000 census, the District of Columbia and North Dakota have shrunk. Massachusetts and New York were estimated to have lost population last year and will join Iowa, Louisiana, Michigan, Ohio, Pennsylvania, West Virginia and others as states that will gain less than 4 percent population in a decade.

The top growth states are again Nevada, which has for the past 35 years been the fastest growing state, and Arizona, which is not far behind. Nevada projects to increase by 43 percent, or 800,000 people, and Arizona by 32 percent, or 1.7 million. Almost half the U.S. population growth will occur in four states: Florida will gain 3.7 million, or 23 percent; Texas 4 million, or 19 percent; California 4.4 million, or 13 percent; and Georgia 1.8 million, or 22 percent. Florida will be larger than New York, Arizona larger than Massachusetts and Georgia and North Carolina larger than New Jersey.

What will all this mean for Congress?

The average congressional district in the next decade will have almost 715,000 people, up from 647,000 after the 2000 census. Compare this to 37,000 per district after the 1790 census and 210,000 per district after 1910 census, when the number of House members was fixed at 435.

Projections are for Texas and Florida to gain three seats, Arizona two and California, Georgia, Nevada and Utah one. Balancing those gains will be losses of two seats each from New York and Ohio and one from Pennsylvania, Massachusetts, Minnesota, Iowa, Illinois, Michigan, Missouri and Louisiana.

Overall, the red or Republican states (won by Bush in 2004) will net a six-seat gain and blue states will lose six. But there is some question whether high-growth, high-immigration states such as Nevada, Arizona and Florida might turn more purple as they grow.

If you are afraid of growth, move to Europe, or to Ohio. But remember that most of your friends are moving to Phoenix, Dallas and Miami, and they’ll have more say in future congresses.

John C. Fortier is a research fellow at AEI.