What could be a good adaption rate for autosuggest / autocomplete?

We have a field for data entry with auto-suggestion / auto-complete. The analytic data says 60% of the users use the options to complete the field. (so 40% of people choose their own answer)

The field is for users to enter their qualification and I assume the suggestion API we have can't cover every existing qualification in the world. Given that people can always choose to write their own answer, I'm just curious of know if there is a baseline for adaption rate. I'd like to know 60% of people choose an answer from the auto-complete is a below or above average.

Could you share your experience or any helpful resource to determine the baseline?