Sourced from National Vital Statistics Reports (Yingzhi Yang/Neon Tommy)

In times of recession, birth rates declined. We saw this in the Great Depression and Oil Crisis. Currently, the economic crisis has put measurable pressure on birth rates in the U.S. 

The U.S. birth rate is slumping—down 0.1 per thousand in 2013 (12.5) from 2012 (12.6). "Birth rates" are total births per 1,000 total population. The U.S. birth rate grew every year from 2003 (14.1) to 2007 (14.3) but declined from 2007 to 2010. "The pace of decline slowed down in 2012," said Brian Karl Finch, professor (research) of sociology at University of Southern California.

However, the number of U.S. births in 2013 was 3,957,577, which was slightly more (4,736) than births in 2012, according to National Vital Statistics Reports. Despite the birth rates decline, the U.S. still remains the third most populous country in the world, after China and India.

Yingzhi Yang/Neon Tommy

In the aggregate chart of 2013 national birth rates and 2013 annual average unemployment rates, the two curves go hand in hand, sharing an almost synchronized opposite rise and fall — the higher the birth rate, the lower the unemployment rate. 

"There is relationship between economic conditions and birth rate in recessions, that is, unemployed people are less likely to have babies because they are scared and don’t think it’s the right time," said Finch.

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Data Sourced from Bureau of Labor Statistics (Yingzhi Yang/Neon Tommy)

But there are exceptions.

Utah's unemployment rate is low and its birth rate is extraordinarily high (17.6), even sort of out of the line. It's not an economic-birth correlation — people have more babies because they have more confidence in the economy — but can be explained as most Utah residents are Mormon, and their church says "God's commandment for His children to multiply," according to Finch. 

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California's unemployment rate (8.9 percent) ranked the fifth highest, while its birth rate (13.1) was also one of the highest.

"Even though different areas were hit differently by the recession in California, it has a large number of immigrants from Latin America, which keeps the birth rate high, regardless of what the unemployment rate looks like," Finch said. 

Reach Staff Reporter Yingzhi Yang here. Follow her on Twitter here.