Classification of Champagne vineyards

The classification of Champagne vineyards developed in the mid-20th century as a means of setting the price of grapes grown through the villages of the Champagne wine region. Unlike the classification of Bordeaux wine estates or Burgundy Grand cru vineyards, the classification of Champagne is broken down based on what village the vineyards are located in. A percentile system known as the Échelle des Crus ("ladder of growth") acts as a pro-rata system for determining grape prices. Vineyards located in villages with high rates will receive higher prices for their grapes than vineyards located in villages with a lower rating. While the Échelle des Crus system was originally conceived as a 1-100 point scale, in practice, the lowest rated villages are rated at 80%. Premier crus villages are rated between 90 and 99 percent while the highest rated villages, with 100% ratings are Grand crus.

Prior to the development of the Échelle des Crus systems, the Champagne industry functioned on a business dynamic that heavily favored the Champagne houses over the vine growers. Since making sparkling wine is a costly and time-consuming endeavor, most vine growers did not have the means or finances to produce Champagne themselves. So instead they would sell their grapes to the Champagne houses who would produce the wines. In a means to generate greater profit, some Champagne houses would look outside the Champagne region for grapes. The development of the French national railroad system in the mid 19th century opened up easy access to cheaper grapes from the Loire Valley and the Languedoc. The Champenois vine growers were incensed at these practices, believing that using "foreign" grapes to make sparkling was not producing true Champagne. They petitioned the government for assistance and a law was based requiring that at least 51% of the grapes used to make Champagne needed to come from the Champagne region itself.

...
Wikipedia