If you think you're seeing fewer babies now, it's not your imagination -- the US Census Bureau says the US population is growing at its slowest rate in more than 70 years, possibly caused by fewer births and less immigration as a result of the recession.

Between April 2010 and July 2011, the country's population increased by an estimated 2.8 million, representing a growth rate of just 0.92 percent, the lowest since the mid-1940s.

What's more, five states accounted for more than half of the total US population growth: Texas, California, Florida, Georgia and North Carolina. Overall, California remains the most populated state with 37.7 million people.

But even with the overall slowdown in the country's population growth, Rhode Island, Michigan and Maine were the only states whose populations declined. And North Dakota's population has reached an all-time high of nearly 684,000 people.

Percentage-wise, the District of Columbia experienced the fastest growth rate, the first time the city led states in growth since the early 1940s.

Harriet Tregoning, DC's planning director, greeted the news with enthusiasm. “I kept saying, please let it not be a bubble,” she said. “Let it really be about growth in the city.”

More From TSM Interactive