It's wholly a self-reporting "test" which means it's all about how you feel when you're taking the test. If you're in a good "mood" you're likely to do better or in a funky mood, not as well. Presumably you'll feel better when you're doing better and that will happen more and more often. So, take it in March and see how you do :-) It's only for your own use, might point out something to you that you hadn't thought about, didn't realize.