(Undated) -- Oregon is listed among the most competitive states when it comes to business tax climate. That's according to the non-profit Tax Foundation's State Business Tax Climate Index, which is based on an analysis of each state's tax code using variables in corporate, individual income, sales, property, and unemployment insurance taxes. Oregon is ranked tenth in the nation for business tax climate. The five most competitive states are Wyoming, South Dakota, Alaska, Florida and Nevada. Washington is ranked 17th.