During Holland's last years in office, New Zealand also faced a serious balance of payments crisis that had been precipitated by a rapid decline in overseas demand for the country's butter, wool, and cheese exports. In addition, Holland's health was proving less and less able to withstand the strain of his duties, and his memory sometimes failed him. Amid the Suez Crisis in October 1956, Holland suffered a mild heart attack or stroke (accounts vary) while working in his office. However, far from retreating to bed, he insisted on remaining at the office for the next 48 hours until the crisis was resolved. According to his biographer Gustafson, Holland's physique never fully recovered from that incident. During the Suez Crisis, New Zealand and Australia were among the few countries to defend the Anglo-French invasion of the Suez Canal.