The status of some states' proposals to change oil and gas severance taxes since 2011:
-- ALASKA: Governor's proposed oil tax cuts failed to gain approval.
-- FLORIDA: Oil production taxes reduced to offset technological costs of extraction.
-- IDAHO: Replaced an existing oil tax with a 2.5 percent conservation tax on the market value of all oil and gas produced.
-- MARYLAND: Two proposals to raise the natural gas severance tax died.
-- MISSISSIPPI: Proposal died that would have changed the way oil taxes are distributed at the state and county levels.
-- NORTH CAROLINA: Environmental agency ordered to study economic and tax implications of oil and gas exploration.
-- NEW MEXICO: Proposed increases on oil and gas production died.
-- OHIO: Governor's proposed severance tax increase on oil, natural gas and natural gas liquids is in negotiation as session continues.
-- OKLAHOMA: Changed tax exemptions on new horizontally drilled and deep wells.
-- PENNSYLVANIA: Attempts to craft a new production tax on natural gas failed to gain approval, as lawmakers opted to impose impact fees instead.
-- VIRGINIA: A proposal to retroactively enact local notification and appeals provisions for coal, gas and road improvement taxpayers back to 2008 fizzled.
-- WEST VIRGINIA: Tax increase on natural gas failed to gain approval, but permit fees were raised.
Sources: National Conference of State Legislatures, AP research