Despite the efforts of health experts, U.S. suicide rates continue to rise. The new findings released from the U.S. Centers for Disease Control and Prevention's National Vital Statistics Report reveal a 24 percent increase between 1999 and 2014. In other words, 10 out of every 100,000 people committed suicide in 1999, and in 2014, this number was 13 per 100,000 people.

"The rate of suicide has gone up nearly steadily since 1999," said Sally Curtin, statistician from the CDC. "It's a broad picture for both females and males. The suicide rate was higher in 2014 than in 1999 for all age groups under 75 years."

For men, the biggest increases occurred in the age group of 45 to 64 years old, whereas for females, the fastest growth during the 15-year report period was in the age group of 10 to 14-year-olds.

Although young women commit suicide less than other age groups, the increase in the youngest group still tripled to 150 total suicides in 2014.

"For this sub-population, these suicides that end in death are just the tip of the iceberg," Curtin said. "For every suicide, we know there are many, many attempts and hospitalizations."

"One of the most salient things the study illustrates is that despite our aggressive efforts to decrease suicide rates, we really haven't been successful," said Maria Oquendo, professor of psychiatry at Columbia University Medical Center. "It's really not clear why it keeps going up."

"With puberty starting earlier and earlier, it's possible some of these kids are experiencing psychiatric conditions earlier," she added. "It's rare for suicide to occur in the absence of a psychiatric condition." 

A possible explanation is the economic downturn, as suicide rates typically rise during tough economic times when jobs are harder to come by. Supporting this idea is the fact that the CDC found a connection between suicide increase and home evictions and foreclosures several years ago.

Another explanation is the abuse of prescription painkillers and other drugs that has risen over the past decade. In fact, the rate of overdose deaths from opioids, such as painkillers, tripled between the year 2000 and 2014, which includes suicides.

Further research needs to be conducted to determine those at risk of suicide and help develop preventative measures for these people.