Vintage, in winemaking, is the process of picking grapes and creating the finished product—wine. A vintage wine is one made from grapes that were all, or primarily, grown and harvested in a single specified year. In certain wines, it can denote quality, as in Port wine, where Port houses make and declare vintage Port in their best years. From this tradition, a common, though not strictly correct, usage applies the term to any wine that is perceived to be particularly old or of a particularly high quality. Most countries allow a vintage wine to include a portion of wine that is not from the year denoted on the label. In Chile and South Africa, the requirement is 75% same-year content for vintage-dated wine. In Australia, New Zealand, and the member states of the European Union, the requirement is 85%. In the United States, the requirement is 85%, unless the wine is designated with an AVA, (e.g., Napa Valley), in which case it is 95%. Technically, the 85% rule in the United States applies equally to imports, but there are difficulties in enforcing the regulation. The opposite of a vintage wine is a nonvintage wine (often seen on a wine list as 'NV'), which is usually a blend from the produce of two or more years. This is a common practice for winemakers seeking a consistent style of wine, year on year. Etymology The word vintage was first used in the early 15th century. It was adapted from the Old French () deriving from the Latin (), in turn coming from () and (). Importance of vintage The importance assigned to vintage is both varied and disputed. For wine produced in regions at the colder climatic limits of wine production, vintage can be very important, because some seasons will be much warmer and produce riper grapes and better wine. On the other hand, a poor growing season can lead to grapes failing to reach optimal ripeness, resulting in grape juice that is higher in acid and lower in sugar, which affects the quality of the resulting wine. In many wine regions, especially in the New World, growing seasons are much more uniform. In dry regions, the systematic and controlled use of irrigation also contributes to uniform vintages. However, such wines are regularly labeled by vintage because of consumer demand. Wines of superior vintages from prestigious producers and regions will often command