The oil and gas industry's share of the assessed property value in Weld County has been on the rise for years: Although 2016 budget planners are enjoying the spoils right now, it looks like the drop in oil and gas activity will take $60 million out of the county's budget in 2017, said Finance and Administration Director Don Warden. A third of the county's revenue comes from property tax, which annually charges a percentage of a property's assessed value, a figure assigned by the assessor's office.