It's possible that there was a state-wide hiring freeze on teachers. State revenues, like federal revenues, declined substantially during the economic downturn. And since education is usually a major part of state budgets, it becomes a primary target for spending cuts if the state government is trying to reduce the amount of debt they're accumulating. A lot of states have balanced budget requirements, but I don't know if Oregon is one. Even if Oregon doesn't have a balanced budget requirement, there will still be substantial political pressure for the state government to reduce spending.