20% of the world's supply of gold, 25% of the world's supply of wheat, 40% of the world's supply of iron and steel, 40% of the world's supply of lead, 40% of the world's supply of silver, 50% of the world's supply of zinc, 52% of the world's supply of coal, 60% of the world's supply of aluminum, 60% of the world's supply of copper, 60% of the world's supply of cotton, 66% of the world's supply of oil, 75% of the world's supply of corn, 85% of the world's supply of automobiles. With the exception of rubber, practically all of the essential raw materials and food products upon which modern industrial society depends are produced largely in the United States. With less than a sixteenth of the world's population, the United States produced from a fifth to two-thirds of most of the world's essential products. 5. _Shipping_ The rapid increase in the foreign trade of the United States created a demand for American shipping facilities. Before the Civil War the United States held a place as a maritime nation. Between the Civil War and the war with Spain the energies of the American people were devoted to internal improvement. With the advent of expansion that followed the Spanish-American War, came an insistent demand that the United States develop a merchant marine adequate to carry its own foreign trade. The United States Commissioner of Navigation in his report for 1917 (p. 78) gives the net gross tonnage of steam and sailing vessels in 1914 as 45 million tons in all. The tonnage of Great Britain was 19.8 million tons; of Germany 4.9 million tons; of the United States 3.5 million tons; of Norway 2.4 million tons; of France 2.2 million tons; of Japan 1.7 million tons, and of Italy 1.6 million tons. The war brought about great changes in the distribution of the world's shipping. Germany was practically eliminated as a shipping nation. The necessity of recouping the submarine losses, and of transporting troops and supplies led the United States to adopt a ship-building program that made her the second maritime country of the world. Lloyd's Register of Shipping gives the steam tonnage of the United Kingdom as 18,111,000 gross tons in June, 1920. For the same month the tonnage of the United States is given as 12,406,000 gross tons. Japan comes next with a tonnage of 2,996,000 gross tons. According to the same authority the United Kingdom had 41.6 per cent of the world's tonnage in 1914 and 33.6 per cent in 1920; while the United States had 4.7 per cent of the world's tonnage in 1914 and 24 per cent in 1920. 6. _Wealth and Income_ The economic advantages of the United States enumerated in this chapter inevitably are reflected in the figures of national wealth and national income. While these figures are estimates rather than conclusive statements they are, nevertheless, indicative of a general situation.