Arapahoe County Treasurer Doug Milliken has been recognized nationally for his investment strategies, which have earned a return more than double the national average for counties.

The Award for Excellence is presented annually by the Association of Public Treasurers of the United States and Canada.

The county’s investment portfolio has taken in about 3.6 percent on total investments so far during 2010. The national average for the year is 1.6 percent.

Milliken credits his investment decisions for generating what has been recognized as one of the highest-earning county investment portfolios in the United States.

“In fact, of the 10,000-plus portfolios we’ve checked, no one comes close to earning as much as we are,” Milliken said. “The higher earnings on our investments translate into lower property taxes for our residents.”

That is due to the Taxpayer’s Bill of Rights. The voter-approved amendment to the Colorado Constitution requires local governments to effectively return some investment income back to taxpayers in the form of lower tax bills.

Milliken is most proud of a much-touted program that he says has helped local businesses spur the economy while generating an improved investment for Arapahoe County.

The treasurer has used more than $18 million of county money to buy certificates of deposit in Arapahoe County banks. The deposits have been contingent upon the banks lending the money to small and medium-sized businesses in the county.

The Award for Excellence was announced at the Association of Public Treasurers’ annual conference in South Carolina.

Milliken, a first-term Democrat, is running for re-election in November. Republican Aurora City Councilmember Sue Sandstrom is his challenger, as she was four years ago.