No predictions loaded for 2099. This site serves NOAA predictions from its own store, and this period has not been fetched for Markham 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/wa/markham-9441098/2099
Markham, WA tide table 2099 (printable) · Tide Almanac