Assessed property values in Colorado are expected to fall for the first time since the late 1980s.

The latest forecast from legislative economists projects that overall assessed property values will drop 5.3 percent this year. Assessed values are expected to dip another 6.9 percent next year.

The report blames a drop in oil and gas prices, the economic downturn and the slow real estate market.

The 1980s decline was blamed on the oil bust and the savings-and-loan collapse.

Property taxes help fund school districts, and  the latest decline will cost the state. According to the forecast, lawmakers, already facing a budget shortfall of up to $1 billion, will have to come up with another $140 million to subsidize schools.