Well, i didn't notice that before...because i'm not often visit here these days.
but one day i found that the rating of one of my old wallpapers( here) has gone down.
It was used to be SS rating and appearred in the showcase.
and now the rating becomes S. It really confused me.
Is it becasuse i'm not active enough or just a bug on the rating system or something else?

Hope someone can answer my question!
Thank you very much!

Wow the rating can actually go down???
at least you start from SS
I only got 1 wall and it's C- T_T

Time is factored into the calculation which creates the opportunity for ratings to go down if their popularity wanes.