I've accepted an offer at a new company, and will be making about 40% more than I currently do. The exit survey from my current employer asks, "if you don't mind sharing," what company I'm going to and what my total compensation will be.
I don't see a downside to disclosing this information to my current employer. It seems like the worst outcome is they do nothing with it. The best case would be they use it to make better-informed compensation decisions in the future. They recently gave most employees a significant "market rate adjustment" based on feedback from an engagement survey.
I suppose some people wouldn't want to disclose this for reasons of personal privacy. That's fair enough, but it's not a concern for me. Are there any other reasons not to answer the question?