Data on search fund success rates? Both funded v unfunded

This is purely anecdotal and would love to know if anyone has any data to support, or hopefully prove me wrong, but it feels like search success has taken a hit. Again just one anecdote, I graduated from business school in 2020 and the amount of failed searches seems quite high vs the typical statement of 2/3rds. Also, is there any data pointing to a discrepancy in success between funded search v unfunded?