The number of road-related traffic deaths in the US state of Arizona have declined to a 16-year low, with 807 traffic fatalities recorded in 2009, according to a report.

The report, released by the US Department of Transportation, highlights that the traffic fatalities in Arizona are at their the lowest since 1993 and down from 938 in 2008.

There were around 1.29 fatalities per million miles travelled in 2009, down from 1.52 in 2008, and the state has also witnessed a 14% decrease in road fatalities in the last two years.

The Arizona Department of Transportation officials credit various factors for the decrease in fatalities, such as enhancements to the roadways and the installation of rumble stripes along freeways, which can reduce crashes by 33%.

Other roadway safety improvements include raised and reflective pavement markers, larger traffic signals on state highways, brighter freeway signs, and guardrail end caps that act as crash cushions, among other measures.