Create a variable @Ratings to store everyone's rating in, then use this trigger to compare ratings and update them.
#TR {^~* ~#%d (%w)%s----~> (%d) ~<Rating~>} {
#IF (%db(@Ratings, %1) <> %2) {#MESSAGE %1's rating has changed from %db(@Ratings, %1) to %2}
#ADDKEY Ratings %1 %2
}
Troubadour