"Between January 2005 and May 2007, 325 ACS patients who underwent PCI and received statins were evaluated. We measured serum lipid levels at baseline and 4 weeks. The relationships between ontreatment levels of triglyceride (TG) and LDL-C and one-year major adverse cardiac events (MACE) were assessed. Results : At 4 weeks, the mean LDL-C level was 72.5±23.8 mg/dL and the mean TG was 123.2±62.8 mg/dL. MACE occurred in 41 cases (12.6%)."
325 / 41 = 12.6, and that's between January 2005 and May 2007. To get annual rate, 12.6 / 29 x 12 = 5.2