Name for the yield of grapes or grapes in the vintage, mostly expressed in hectoliters grape or wine per hectare or kilogram of grapes per hectare. Overseas is too tons / acre common. This is also called wine law Target, expressed as maximum yield in hectoliters per hectare, used for certain wine quality grades and may vary widely depending on the country, wine-growing region, individual locations or even specific wines. In terms of grapevine density, there has been an extreme reduction in the last two millennia. The Romans still recommended 50,000 vines per hectare; this excluded from the outset a mechanical processing of the vineyard. In the middle of the 19th century, the average density was still 20,000 vines per hectare, with yields of at most 40 hectoliters per hectare. Today, the vines are set at a distance of 1.5 to 2 meters (different for each country and wine-growing region, as well as depending on regional requirements).