The number of overall traffic fatalities in the U.S. declined in 2013 from the year before while those involving commercial trucks turned just slightly higher, according to newly released figures from the National Highway Traffic Safety Administration.

Its Fatality Analysis Reporting System shows a 3.1% drop from the previous year and a nearly 25% decline in overall highway deaths since 2004. In 2013, 32,719 people died in traffic crashes. The estimated number of people injured in crashes also declined by 2.1% to 2.3 million.

The decline in traffic fatalities continues a long-term downward trend leading to the fatality rate matching a historic low of 1.10 deaths per 100 million vehicle miles traveled in 2013, down from 1.14 deaths per 100 million vehicle miles traveled in 2012.

There was a 0.5% increase in the number of people killed in crashes involving large trucks, totaling 3,964. The number of large-truck occupants who were killed totaled 691 while the number of occupants of the other vehicles who were killed totaled 2,834, both decreasing by less than 1%. It also marked the fourth straight yearly increase in truck involved crash deaths since hitting a low in 2009.

The number of non-occupants killed during a large-truck crash increased by 13%, or 49 people, from 2012 to 439 in 2013.

NHTSA noted that the number of fatal crashes involving large trucks is relatively small compared to those involving other vehicles, so even small changes in the numbers of fatalities may result in large percentage changes.

Other key statistics include:

• The number of passenger vehicle occupants killed in crashes declined by 3% to 21,132, the lowest number on record dating back to 1975. Passenger vehicles include passenger cars, SUVs, minivans and pickup trucks.

• Motorcyclist fatalities declined 6.4%, the first drop since 2009.

• Pedestrian fatalities declined by 1.7% to 4,735, but remains 15% higher than the record low of 4,109 pedestrian fatalities in 2009.

• Bicyclists fatalities increased by 1.2%, the highest since 2006.

• The number of people killed in distraction-affected crashes fell to 3,154 in 2013 from 3,380 in 2012, a 6.7% decrease. However, the estimated number of people injured in distraction-affected crashes, 424,000, increased by 1% compared to 2012.

• Alcohol-impaired-driving fatalities decreased by 2.5% in 2013 to 10,076, but still accounted for 31% of the overall fatalities in 2013.

• Thirty-four states experienced reductions in overall traffic fatalities, led by Ohio, Kentucky, Pennsylvania, South Carolina and Arkansas

The Fatality Analysis Reporting System contains data for a census of fatal traffic crashes within the 50 states, the District of Columbia, and Puerto Rico. To be included in FARS, a crash must involve a motor vehicle traveling on a roadway customarily open to the public and must result in the death of at least one person, either an occupant of a vehicle or a non-motorist, within 30 days of the crash. The FARS data goes back to 1975.

A further summary of the findings is available on the NHTSA website.