Number of millions of barrels of Bourbon currently aging quietly along in Kentucky. This year has been a particularly spectacular year for bourbon production, according to the Drinks Business. However, thanks to an old Kentucky state law which considers full barrels of bourbon as property, all of that bourbon is taxed–every year (like real estate). Kentucky distillers are braced to pay $33 million in “barrel aging taxes” this year alone. No other region in the world taxes spirits in the same way.