Large Erroneous numbers
On the Dashboard, some users may see "Days since last flight" as random large numbers (which are not correct or do not make sense).
This occurs if you have ANY logbook entries which have an Aircraft Type entered, but with no associated hours for those entries.
This is common for users who tend to copy/drag a long list of "C152" and "Self" in the appropriate columns to avoid repeat typing (this is a great idea to decrease your workflow), but only do it when you are entering the hours at the same time.
Remove all blank logbook entries (with an Aircraft Type, but with no hours).
Numbers App Compatibility
The "Days since last Flight" is a known issue with "Numbers" and is unfortunately not compatible.
#NAME
Older versions of Microsoft Excel will cause this formula to display #NAME
Please update your program to the latest version or use Google Sheets.