That actually helps a lot!!
I will see if the conversion was over 5 percent and check the tide info too.
I do have a follow up tide gage question. In the NOAA tide gage database there are some gages that are no long active but still have the old readings, however, they did not have NAVD88 reading like the active gages. Is there an alternate way to find a NAVD88 figure so one can use this old tide gage data or does it become invalid once NOAA stops recording data?