If your decision to stop having children has to do with the concept of overpopulation, feel free to continue breeding. According to the Centers for Disease Control and Prevention, American women are having fewer babies than ever — and this might not be a good thing for our nation.

In a new report released this week, the CDC revealed that the national total fertility rate (TFR) — basically an estimate of how many babies the average woman will have — is down. In 2017 it was 1.7655, while in 2016 it was 1.8205 and in 2015, 1.8435. While the variances might seem insignificant, the government agency maintains it is not.

To reproduce itself and maintain a stable U.S. population, a TFR of 2,100 births per 1,000 women is necessary. So basically, women either need to have more babies or immigration needs to increase.

The CDC also broke down TFR by state, which as you can imagine, greatly varies. It is highest in South Dakota with 2.2275 and lowest in the District of Columbia with 1.4210. It also is dependant on race, with Hispanic women boasting a higher TFR at 2.0065. The only states that are procreating enough to sustain the population are South Dakota and Utah.

There are many reasons offered to explain the decrease in TRF including fewer teen pregnancies, changing economics, greater availability of contraception and the fact that most of the population is waiting until they are older to have children.

“In general women are getting married later in life,” public health researcher John Rowe at Columbia University told NBC News, “They are leaving the home and launching their families later.”

Dr. Helen Kim, an associate professor at Northwestern University’s Feinberg School of Medicine, also pointed out that the idea of the ideal family size has changed over the years. “There are shifts where having smaller families is a trend,” she added. “I can’t speak on this as a sociologist, but this is what I’ve seen among my peers and colleagues.”

While you shouldn’t go out an procreate just because of this report, if you do decide to have a bigger family — or someone tries to throw that overpopulation argument at you — at least you won’t have to feel as guilty about it!

READ NEXT: Fertility Rates Down Across The US Now That First-Time Moms Are Older