If they are truly missing and you do not have a backup/older copy of the
file, then the data is lost.

However, before tying the rope to the cieling beam, try making certain that
it really is gone:
Open the book and save it with a new name.
Select a row by clicking on any row number and use Format | Columns and make
sure that none are hidden.
After making sure that no columns are hidden, select all cells by clicking
the blank gray square just above the [1] row number and left of the [A]
column indicator then use Edit | Clear and choose [Formats] - this would
cause any entries set in very small font size or that had their font color
set to the background color to make them appear invisible.

Good luck.

"semloh2" wrote:

When I opened worksheet, about 5-10 columns of stored data were missing. They
should have been to the left of the data I was looking at. Is retrieval
possible, and if so, how? Thanks.