just to add you may have state tax exemption from US territories also if the fund had exposure to Puerto Rico etc, so it may be a few entries in addition to "Multiple States" to get the full benefit on your state taxes, but certainly not all 50+ are needed.
See this similar post here with more details from @SteamTrain on how to enter this
https://ttlc.intuit.com/community/taxes/discussion/re-1099-b-box-12-which-state-is-your-exempt-inter...
