Infantry 15% of the Marine Corps

Every Marine is a Rifleman 

"the Marine Corps infantry accounts for over 21,600 active duty and 7,200 reserve Marines—roughly 15 percent of the Corps."

https://www.usni.org/magazines/proceedings/2020/october/marine-corps-infantry-dilemma#:~:text=This%20requires%20no%20small%20amount,15%20percent%20of%20the%20Corps.

"Infantry Soldiers make up 15 percent of the Army force."

https://www.army.mil/article/45200/