OKLAHOMA CITY (AP) — Overall revenue collections to the Oklahoma treasury declined for the 18th consecutive month in August, Oklahoma Treasurer Ken Miller reported on Tuesday, while state unemployment has exceeded the national rate for the first time in 13 years.

Gross receipts to the state treasury declined 4 percent last month compared to the same month in 2015, while collections over the past 12 months were off by more than 7 percent compared with the prior period. Miller, an economist, said he has yet to find any indication that the state's economic slump over the last two years shows any...