In Chronique (souvent) Bordelaise you can read about the evolution of harvest yields in Champagne. When the appellation was created in 1935 the maximum yield was defined as 7500 kg/hectare. (In Champagne they count in kg/ha instead of the measure hectolitres/ha used in most other districts. 7500 kg/ha corresponds to approx 50 hl/ha.)
By 1998 they maximum yield had reached 8500 kg/ha (ca 57 hl/ha).
Today the allowed harvest volume is (after the latest increase earlier this year) 15,500 kg/ha (ca 103 hl/ha).
A curious contrast to most other regions that make efforts to restrict yields to increase quality.
Update 2025-07-31:
The graph below shows an estimate based on reported numbers of the evolution of harvest yields in Champagne from 1919 to 2021. The graphic is from BKWine’s book on Champagne, Champagne, the Wine and the Growers (Champagne, vinet och odlarna). This is based on reported harvest volume and reported vineyards acreage. It does not show the maximum yield set each year.
