The shocks that reverberated from the battlefield continued to widen: On 18 February 1968 MACV posted the highest U.S. casualty figures for a single week during the entire war: 543 killed and 2,547 wounded. As a result of the heavy fighting, 1968 went on to become the deadliest year of the war for the US forces with 16,592 soldiers killed. On 23 February the U.S. Selective Service System announced a new draft call for 48,000 men, the second highest of the war. On 28 February Robert S. McNamara, the Secretary of Defense who had overseen the escalation of the war in 1964–1965, but who had eventually turned against it, stepped down from office.