[PLUG] RE-introduction to spreadsheets after decades ;/

[Richard Owlett]

I've not used a spreadsheet in THIS *CENTURY*.
I have forgotten much.

I'm using Gnumeric on Debian and have successfully imported ~280 lines 
of data.

The first column is a date.
https://help.gnome.org/users/gnumeric/stable/gnumeric.html says:
> Gnumeric stores the value as the number of days since the first day
> of January in 1900. 
I want the second column to display days since 1/1/2008.
Should be simple :<
Just enter the formula "A1 - 35921" in cell B1,
then copy column B.

*BUT* Gnumeric then asks if I really want to copy it >65000 times.
Of course not.
I only have ~280 lines in *MY* view.

Is there a simple way?
TIA