Why there is no rating before 1997 on the chart into rating section from account ?
If I understand your question correctly, I think I can provide a helpful answer.
If you go, on your TMDb profile page, to your Ratings & Reviews tab, click on that, place your cursor over the Ratings By Year grid, then scroll downward (being sure that the cursor remains over the grid area the entire time). Doing so will scroll the grid back into earlier years and decades, to as far back as the year 1900.
Try that and see if it achieves the result you're seeking.