(Salem, OR)  --  State officials say Oregon's four-year high-school graduation rate improved last year to 72 percent.  But "The Oregonian" reports a change in the definition of a high-school graduate accounted tor the improvement from 2013.  Oregon expanded its graduation definition to include special education students who earn modified diplomas and students who defer receiving their diplomas so they can attend a year of community college for free.  Washington's high-school graduation rate rose one-point-two percentage points last year, improving the four-year rate to 77-point-two percent.