The auxiliary unit of measurement for ratios is used to represent proportions in percent (Latin per cento = of one hundred, hundredth). In viticulture, ratios play a role in two areas in particular.
Regarding the slope or steepness of a vineyard (steepness) see under:
For the alcoholic strength of an alcoholic beverage, see under:
Table: Norbert F. J. Tischelmayer
In the past, you needed a wealth of encyclopaedias and specialist literature to keep up to date in your vinophile professional life. Today, Wine lexicon from wein.plus is one of my best helpers and can rightly be called the "bible of wine knowledge".
Prof. Dr. Walter Kutscher
Lehrgangsleiter Sommelierausbildung WIFI-Wien