More Americans are dying, a new report shows.
For the first time in many years, the overall death rate ticked up in 2015, according to new federal data.
It's not clear why and experts have to go through and analyze the data a little more thoroughly before they can say where and in which groups the deaths rates rose. But the initial data for 2015 from the National Center for Health Statistics shows the adjusted death rate went up from 723 deaths per 100,000 people in 2014 to nearly 730 deaths per 100,000 in 2015.
"Among the causes of death included in this report, increases between 2014 and 2015 in both crude and age-adjusted death rates were observed for Alzheimer's disease, chronic liver disease and cirrhosis, chronic lower respiratory diseases, hypertension, Parkinson's disease, septicemia, homicide, firearm-related injury, suicide, and unintentional injury and drug overdose," the NCHS, part of the Centers for Disease Control and Prevention, said in its report.
These death rates are age-adjusted, meaning the age of the population is taken into account so that it doesn't appear that deaths rates rose simply because one group of people happened to be older than another group, for instance.
If the trend continues as the data is analyzed, and if it's seen again next year, then health officials will know something is changing.
One area that doctors know is a problem is suicide. Just weeks ago, the CDC reported that suicide rates went up in 2014 and had risen by 24 percent since 1999, to 13 suicides for every 100,000 people.
The new data shows the trend continued. "The crude death rate for suicide for the 12-month period ending with the third quarter of 2015 was 13.6 per 100,000 population, higher than that for the same period of 2014 (13.2)," the NCHS report reads.
"The age-adjusted death rate (from suicide) was higher in 2015 than 2014 (13.1 and 12.7, respectively) for the comparable period."
The new data also indicates a big increase in death rates from Alzheimer's disease. In 2014, 25.4 people in every 100,000 died from Alzheimer's. This went up to 29.2 in 2015. However, Alzheimer's is not consistently listed as a cause of death, especially when someone who dies has many conditions. People with Alzheimer's can die of heart disease, pneumonia from inhaling solid food, and other causes.
Gun deaths also went up, from 10.5 per 100,000 in 2014 to 11.2 in 2015.
The NCHS simply collects the data and does not gather details on why the changes might be happening.
The last complete and fully analyzed report on deaths in the U.S. came in 2013, when 2.6 million Americans died. The crude death rate was 821.5 deaths per 100,000 and the average life expectancy was 78.8 years. The crude deaths rate — not adjusted for age — was 841.9 per 100,000 population in 2015.
That's still way down from 2001, when the crude death rate was 855 per 100,000. And in 1900, the yearly death rate was one in 42 — or 2,381 deaths per every 100,000 people.
This article originally appeared on NBCNews.com.