By Randy Ellis Staff Writer rellis@oklahoman.com Bolstered by an improving economy and increased oilfield activity, the Oklahoma state treasury has taken in a record $12.8 billion in gross tax receipts over the last 12 months, State Treasurer Ken Miller announced Wednesday. Those collections are $1.5 billion, or 13.1 percent, more than collections from the previous 12 months, he reported. The previous record for a rolling 12-month period was $12.7 billion set at the end of October. “The economy continues to propel treasury collections,” Miller said.Read more on NewsOK.com