By May 1945, 96% of all tactical troops were overseas. No new units were forming and there were no reserves. Fortunately, these sufficed to bring about the defeat of Germany and Japan, largely because the Soviet Union carried most of the burden of fighting the German Army on the Eastern Front. However, it also meant that divisions were kept in the line longer than anticipated and took heavier casualties. In three months of intensive combat, an infantry division could expect 100% casualties in its three infantry regiments. Units were maintained by a continuous flow of individual replacements. Such conditions placed great strain on the combat soldier who remained in action until he became a casualty.