States’ Nonconformity with Federal Measurements Creates “Barrels” of Compliance Costs
Many states levy taxes on liquids on a per-barrel basis. However, some states define a “barrel” differently than the standard measurement. The landscape of unharmonious units creates complexity and compliance costs for businesses that must pay these taxes in multiple states.
We haven't written up this one. Tax Foundation has the full story — the link below goes straight to it.