No predictions loaded for 2001. This site serves NOAA predictions from its own store, and this period has not been fetched for Fort Sumter yet. Nothing is estimated or interpolated in its place. NOAA's own page for the station has the official table: tidesandcurrents.noaa.gov.
tidealmanac.site/us/sc/fort-sumter-8665728/2001
Fort Sumter, SC tide table 2001 (printable) · Tide Almanac