It doesn't change. That's the reason score is taken into account rather than the marks obtained out of 100 in GATE exam.

The score is formulated using normalisation formula mentioned in the scorecard which makes it valuable enough to be compared for next 3 years including the current one.

GATE Score (out of 1000) is mainly used for admission to masters degree and it is valid for 3 years.

You will be compared with respect to your score, with other applicants and it will having the same value throughout its validity. Best of luck!!

I hope you got your answer.