I have the same feeling. When this aspect is neglected for more than a year it just seems no one's bothered.
It's a shame LMI can't maintain this.

Usually they are refreshing ratings at a start of a year and give a one-time update for the year as I observed it in the past few years.
I share rajeshk's opinion and it would be great to see how are ratings change from test to test both sudoku and puzzle.