bb!
I highly doubt that GMAC resluts are comparable for last 5 years. People who took the test five years ago did not experience this level of difficulty (especially not in Q), I can bet money on it. It could never be scientifically proven though, since people who took the test 5 years ago are no longer the same people as far as intelligence is concerned. A jump or a decent in scores if they take the GMAT now could easily be explained by GMAC or ETS.
My tests were only two and a half month apart. First time when I took the test I only studied the Kaplan for couple of weeks and took one Kaplan exam and one PP exam and did not even practice any probability or comb/perm stuff. I did not encounter any one of them in my last exam and that explains my 47 score. Even few weeks ago only people scoring in the 48-50 range saw those problems. Something changed during the month of July and people started reporting weird experiences like a COMB problem on the 3rd question, 2/3 prob./comb./perm problems even if they are scoring 43/44 and like a lot of other people, I also thought that they must have misiterpreted something.
I can tell you one thing, GMAC/ETS must have changed their whole philosophy about the test recently, probably to decrease the number of people with really high scores or to maintain the shape of their much beloved Bell curve. But, the thing is that it is not fair to the people who might be preparing based on the previous materials and information. They will definitely be shocked. Some would get over it and others might screw it up. Most recent materials including PR, KAplan are not familiar with this test philosophy and they would probably revise and make more money at it. Here you go it is more money for everyone, including GMAC and ETS who are experiencing a slump in the number of test takers.
I know I should not have scored this low, even if ETS is playing tricks with us. In my undergrad life I took about 8 Math classes including all Calculus classes and I have an A in every one of them and the highest in the class in most of them. Not having enough sleep would affect your concentration and make you do silly things. But, the whole idea behind the CAT is to figure out where my level is and I can tell you one thing that CAT did a really s***** job at it. I know nobody would have believed me if I had not scored the 690 on the first exam, but I proved to CAT before than I can handle the difficulty or CAT thought I did and if that is not the case, then CAT did a crappy job that time also, suggesting CAT is not consistent in measuring capabilities.
Please be alert when you are taking the test and if you do not get up at 6 in the morning everyday, please do not sign up for an 8 A.M. session.
Good luck.
mbaforme