@Queenie, from a quick google and my understanding each trait that the test measures is based on a percentage rather than a definite one way or the other. The results are often conveyed and understood as being one or the other of a particular trait, but if examined in detail they will show how strongly one is aligned with each trait. From that, it seems as if any variance in 'type' over time, is likely to occur because of factors including mood, environment, habits at the time etc. I know for me the I. N and F will come up high almost always. I don't score as highly in my P trait so I would imagine over time it's going to be the one most likely to change, like Spooky with your I/E. There's some really interesting articles out there written by people who believe that traits that are too developed or underdeveloped can present challenges, and then how to work on those traits to become more 'rounded'.