In 1939 the active United States military totaled 335,000, and during World War II more than 16 million men and women served, while tens of millions more served in the armed forces of other nations. By the war's end America had sustained 1,000,000 casualties, including nearly 300,000 killed and 700,000 wounded. Worldwide, estimated military and civilian deaths exceeded 53,000,000. In countries where battles were fought, millions of people were left homeless and entire cities and towns had to be rebuilt. The United States lost 59,000 aircraft, 157 naval vessels, and 866 merchant ships, while worldwide more than 254,000 aircraft were lost and more than 11,000 naval and merchant ships sank to the ocean floor. The direct economic cost to the world was estimated at one trillion six hundred million dollars.