The Association of American Medical Colleges (AAMC) compiles data on active U.S. physicians and publishes its results in the Physician Specialty Data Book. From that document, 13.6% of active U.S. physicians specialize in internal medicine and 8.67% of active U.S. physicians are under age 55 and specialize in internal medicine. What percentage of active U.S. physicians who specialize in internal medicine are under age 55?