How safe is it to idle/cruise/light throttle in the low 15's? After logging many drives I noticed that my a/f jumps between 14.4-15.2 at idle and steady cruising. I know 14.7 is the target but am I causing any harm being in the low 15's?

Also, under light throttle I see 15's and sometimes 16.1.

Am I causing harm to my motor under these light load conditions?