Vintages
The term vintage has a distinct meaning in the context of vintage port. While a vintage is simply the year in which a wine is made, most producers of vintage port restrict their production of year-labeled bottlings to only the best years, a few per decade.
If a port house decides that its wine is of quality sufficient for a vintage, samples are sent to the IVDP for approval and the house declares the vintage. In very good years, almost all the port houses will declare their wines.
In intermediate years, the producers of blended vintage ports will not declare their flagship port, but may decide to declare the vintage of a single quinta, e.g. the 1996 Dow's Quinta do Bomfim and Taylor's Quinta de Vargellas. Some houses now choose to declare their wines on all but the worst years: Quinta do Vesuvio has declared a vintage every year with the exceptions of 1993 and 2002.
Improved wine making technologies and better weather forecasts during the harvest have increased the number of years in which a vintage can be declared. Although there have been years when only one or two wines have been declared, it is over thirty years since there was a year with no declarations at all.
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