Rating System

I think that a rating system would be good to have, to let readers know what we think of the Debka info in question. Personally, I am inclined to a letter ranking system, like a grade, for either school or bonds. A, B, C, D, and F, with A being highest and F being lowest. My initial idea is this:

A: High chance of it being accurate
B: Good chance of it being accurate, over 50%
C: So, so chance of it being accurate, split 50-50
D: Poor chance of it being accurate, less than 50%
F: Total nonsense, almost certainly inaccurate

+ and - could be used to qualify them as needed.