Staples Inc., the world’s largest office-supplies chain, slumped the most in a year after cutting its annual profit forecast because of declines in its retail and international business. Framingham-based Staples had gained 48 percent this year through Tuesday, compared with a 16 percent increase for the Standard & Poor’s 500 index. The stock fell $2.57, or 15.29 percent, to close at $14.27.
Staples, which suffers from waning consumer demand for products like ink, toner, and computer accessories, cut its outlook after second-quarter results were weaker than it expected. Chief executive Ron Sargent said drops in international operations countered online growth and cost management. International sales fell 8 percent in the period ended Aug. 3.