In Champagne, a wine labeled with a year on it (Vintage) must only contain grapes grown in that year. But vintages vary from every vineyard and for every kind of wine grape harvested, so to maintain a consistent house style from year to year — something Champagne is particularly renowned for — they blend various vintages together to make the Champagne taste the same each year. These Champages are labeled as N.V. and it is recommended they be consumed within 5 years of production.