By Tony Romeo

PHILADELPHIA (CBS) — Pennsylvania State Police say the overall number DUI arrests they made increased last year, while the number of arrests for driving under the influence of drugs skyrocketed.

Overall, the 18,801 DUI arrests by Pennsylvania State Police last year represent an increase of 6.2 percent compared to 2014.

But the eye-popping statistic was a staggering 43-percent increase in the number of arrests for driving under the influence of drugs, which accounted for nearly a quarter of all DUI busts in 2015.

Trooper Adam Reed credits increased training and use of “drug recognition experts.”

“These experts, or DREs as we call them, respond and do specialized testing on an individual that the officer may believe is under the influence of a drug while driving a vehicle.”

The State Police DUI numbers for 2015 do not include statistics from other law enforcement agencies in Pennsylvania.