the 1950s, Schwinn began to aggressively cultivate bicycle retailers, persuading them to sell Schwinns as their predominant, if not exclusive brand. During this period, bicycle sales enjoyed relatively slow growth, with the bulk of sales going to youth models. In 1900, during the height of the first bicycle boom, annual United States sales by all bicycle manufacturers had briefly topped one million. By 1960, annual sales had reached just 4.4 million. Nevertheless, Schwinn's share of the market was increasing, and would reach in excess of 1 million bicycles per year by the end of the decade. In 1946, imports of foreign-made bicycles had increased tenfold over the previous year, to 46,840 bicycles; of that total, 95 per cent were from Great Britain. The postwar appearance of imported "English racers" (actually three-speed "sport" roadsters from Great Britain and West Germany) found a ready market among United States buyers seeking bicycles for exercise and recreation in the suburbs. Though substantially heavier than later European-style "racer" or sport/touring bikes, Americans found them a revelation, as they were still much lighter than existing models produced by Schwinn and other American bicycle manufacturers. Imports of foreign-made "English racers", sports roadsters, and recreational bicycles steadily increased through the early 1950s. Schwinn first responded to the new challenge by producing its own middleweight version of the "English racer". The middleweight incorporated most of the features of the English racer, but had wider tires and wheels. The company also joined with other United States bicycle manufacturers in a campaign to raise import tariffs across the board on all imported bicycles. In August 1955, the Eisenhower administration implemented a 22.5% tariff rate for three out of four categories of bicycles. However, the most popular adult category, lightweight or "racer" bicycles, were only raised to 11.25%. The administration noted that the United States industry offered no direct competition in this category, and that lightweight bikes competed only indirectly with balloon-tire or cruiser bicycles. The share of the United States market taken by foreign-made bicycles dropped to 28.5% of the market, and remained under 30% through 1964. Despite the increased tariff, the only structural change in foreign imports during this period was a temporary decline in bicycles imported from Great Britain in favor of lower-priced models from the Netherlands and Germany. In 1961, after a successful appeal by bicycle importers, the Eisenhower tariffs were declared invalid by the Court of United