The birth rate in the United States is in decline, but at the same time, the vast majority of Americans say they want kids.

Even though the vast majority of Americans say they have, want or wish they had kids, the reality is that fewer children are being born in the United States. A new Gallup survey suggests financial pressures are one reason for the trend.

Americans' views about having kids have hardly changed since 1990: More than nine in 10 adults today say they have kids, are planning to have kids or wish they had kids, a new Gallup survey found. Just 5 percent say they don't want children; 4 percent said the same in 1990.

Despite these barely-changed attitudes, the U.S. birth rate has dropped 11 percent since 1990. In 2011, the fertility rate in the United States fell to an all-time low, at 63.2 births per 1,000 women between ages 15 and 44, according to a report from the Centers for Disease Control and Prevention (CDC). In 1990, the fertility rate was 70.9 births per 1,000 women. [10 Scientific Tips For Raising Happy Kids]

The new poll results were collected between Aug. 22 and 31, from a nationally representative sample of 5,100 American adults. When asked, "What do you think are the main reasons why couples do not have more children?" most survey respondents mentioned financial reasons.

Sixty-five percent cited not having enough money or the cost of raising a child, and another 11 percent listed the state of the economy and lack of job opportunities in the United States. Six percent said they thought not having kids, or not having more kids, was likely due to a personal choice, or a lack of desire for children.

If American's opinions truly reflect the reasons for the drop in birth rate, Gallup says there's reason to believe the birth rate will rise again.

"Because many of the reasons Americans mention for couples not having more children are related to finances and the state of the economy, it is possible that economic improvement will activate the nearly universal desire for children — and thus correspond with an increase in the fertility rate," Gallup officials wrote in a statement.

The poll also found that 53 percent of Americans between ages 18 and 40 have children, and another 40 percent do not have kids, but said they hope to have them in the future. Just 6 percent in this age group don't have and don't want kids.

Among Americans ages 45 or older, 86 percent have kids, and nine in 10 of that group said they would "do it over again." Of the 14 percent of Americans over age 45 who are childless, half said they would have at least one child if they had to do it all over again.

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