In most cases, we taste hundreds of wines before rating a vintage; at a minimum, for small subregions, we sample dozens of wines. Few wines are released in the same year that the grape harvest took place. Exceptions include Beaujolais Nouveau, which is meant for immediate consumption, and some white varieties from the Southern Hemisphere, where the fall harvest takes place in the first half of the new year--the opposite of Northern Hemisphere regions. These wines likewise are typically meant for early drinking; our charts focus on regions and grapes from which a substantial amount of ageworthy wine is made.

Many other wines--whites and reds--spend at least a few months to a year developing in tanks or barrels and then in bottle before being shipped to stores. Other wines, such as Barolo, Barbaresco and Brunello, are required by law to be aged for years before release; our charts display the vintages available in the market. We do not provide a vintage rating until we have blind tasted a sufficient number of bottled wines.