Prohibition in the United States was a measure designed to reduce drinking by eliminating the businesses that manufactured, distributed, and sold alcoholic beverages, however instead of the positive changes in society that were expected, in many ways this plan backfired. The Eighteenth Amendment to the US Constitution took away license to do business from the brewers, distillers, and the wholesale and retail sellers of alcoholic beverages. The leaders of the prohibition movement were alarmed at the drinking behavior of Americans, and they were concerned that there was the beginning of a drinking problem that was spreading. The prohibition movement's strength grew, especially after the formation of the Anti Saloon League in 1893. The League, and other organizations that supported prohibition such as the Woman's Christian Temperance Union, soon began to succeed in enacting local prohibition laws. Eventually the prohibition campaign was a national effort. During this time, the brewing industry was the most prosperous of the beverage alcohol industries. Because of the competitive nature of brewing, the brewers entered the retail business. Americans called retail businesses selling beer and whiskey by the glass saloons. To expand the sale of beer, brewers expanded the number of saloons. Hard-pressed to earn profits, saloon owners sometimes introduced other vices such as gambling and prostitution into their establishments in an attempt to beat out competitors and earn profits. Many Americans considered saloons offensive, distasteful institutions. The best evidence available to historians shows that consumption of beverage alcohol declined dramatically under prohibition. In the early 1920s, consumption of beverage alcohol was about thirty per cent of the pre-prohibition level. Consumption grew somewhat in the last years of prohibition, as illegal supplies of liquor increased and as a new generation of Americans disregarded the law and rejected the attitude of self-sacrifice that was part of the foundation of the prohibition movement.