I took the GMAT 3 times last year and one time in 2013.
My very first GMAT score was 560 and I got this with about 1 month of self-preparation. I had used only the
OG and Foundation of Math by Manhattan.
2 1/2 years later I started preparing again for the GMAT.
It took me forever to break through the 600 despite hours and hours of studying with different test companies.
I achieved my best score in July of last year with 630. Well, I thought I could do better so I continued studying and took the GMAT one last time in early October.
Between July and October I had finished another online class, 40 tutoring hours, solved thousands of problems and what not.
The result was heartbreaking. After 9 months of intense studying I got my lowest score ever: 530. Ouch!
I was so shocked but realized what the problem was immediately. By my fourth attempt I was completely mentally fatigued and had developed test anxiety.
I was ready to give up and probably still am. Not sure where I am right now.
Anyway I took my 630 and submitted my applications at the end of last year. I once tried to open the
OG during the last 3 months and it made me feel nauseous. Not kidding!
Well, I am not sure what happened today. I decided to take an official practice exam "just for fun." I wanted to see where I stood in terms of knowledge.
610! Now isn't that funny? I haven't looked at a single GMAT problem in 3 months and scored 80 points higher than on my last official exam.
To me this means that I still remember a few things or I was just lucky guessing today?
Either way, all I am saying, yes there can be extreme fluctuations. I depends on SO much and NEVER underestimate test anxiety. It's a real thing!
I did not believe this because I never had test anxiety once when I was in college. I always thought it was just a lame excuse of students who had not studied. Well, sometimes it may be, but test anxiety DOES EXIST!
Good luck!