User blog comment:Shinhwalee/World 4-3 Power Level Guide for DD & CL/@comment-26274033-20150416065727/@comment-24930367-20150416071254

I think it's normal, especially if your fleet is a frequent visitor to J-node.

That, and scratches from enemy ships piles up, even from those supposedly 'harmless' preemptive torpedoes (I've got my Akagi knocked down to moderate from one of those).