average rank in the usmc
In 2012, Army and Marine Corps officers reached the rank of O-5 (lieutenant colonel) at 16.5 years, on average, compared to 14.6 years for Air Force and 14.9 years to make Navy commander. The Defense Department overall average of 15.4 years to 0-5 was very close to the average of 15.6 reported in 2000.