How can i protect a formula and still allow copy and move data?

i have 12 columns with data on days and each new day i want to add a new day
to the set of 12 columns without adding a 13th one. So the oldest day are
removed and the view is still 12 days.
In these columns some values are calculated with formulas from data residing
in the column (not from other columns) and i want to protect the formula but
allow the column to be moved one step to the left.
As of now i havent been able to use the built in functions of protection of
cells and protection of formulas.
Any ideas?