An estimated 6,227 pedestrians lost their lives on U.S. roads in 2018, representing a 4% increase over the 5,977 deaths in 2017 and the highest number of pedestrian fatalities in nearly three decades.

The latest figures come from a new report from the Governors Highway Safety Association that offers a first look at pedestrian traffic deaths based on preliminary data provided by 50 state highway safety offices.

Pedestrians are projected to account for 16% of all traffic fatalities in 2018 as compared with just 12% 10 years ago, according to the report.

Experts, including the National Safety Council, say the trend is troubling. From 2008 to 2017, pedestrian fatalities increased by 35% nationwide — yet during the same period, all other traffic deaths combined decreased by 6%.

States reported a range of changes in the number of pedestrian fatalities in the first half of 2018 compared with the same period in 2017.

There was some promising news. For example, 23 states saw declines in pedestrian fatalities for the first half of 2018 compared to 2017, with six states reporting double-digit declines and three reporting consecutive years of declines. Additionally, sharp decreases in pedestrian fatalities in some cities suggest that state-level data may obscure local success stories.

Even so, 25 states and the District of Columbia experienced increases in pedestrian fatalities in 2018, and two states remained the same.

Five states — Arizona, California, Florida, Georgia and Texas — accounted for nearly half (46%) of all pedestrian deaths. California reported the highest number of pedestrian fatalities (432) in the first half of 2018, and New Hampshire had the fewest, reporting just one.

Seven states — California, Florida, Texas, Georgia, Arizona, New York and North Carolina — are each expected to have more than 100 pedestrian deaths in 2018, an increase of two states over 2017.

The report also explores the many factors that are causing a spike in pedestrian traffic deaths.

These include more Americans walking, which increases overall exposure. In addition, unsafe driving behaviors, such as speeding, distracted and drowsy driving, all pose risks to pedestrians. Moreover, alcohol impairment by the driver or pedestrian was reported in about half of traffic crashes that resulted in pedestrian fatalities in 2017.

The report also notes that most pedestrian fatalities take place on local roads, at night, away from intersections — suggesting the need for safer road crossings. Over the past 10 years, nighttime crashes accounted for more than 90% of the total increase in pedestrian deaths.

Another trend concerns sport utility vehicles. The number of SUVs involved in pedestrian deaths has increased by 50% since 2013. By comparison, (non-SUV) passenger cars' involvement in pedestrian fatalities increased by 30% over the same time period. Although passenger cars still account for the majority of pedestrian deaths, SUVs make up an increasingly large percentage.