copying a file every few minutes.

hi people,

needless to say i'm new to excel( its too advanced for me, ha ha). SO need help.

i want to do the following automatically,

a) every 3 minutes, copy an excel file that is updated every few minutes,

in this new file i want to:-

b)replace two columns 'A' and 'B' with one column 'A'
c)latest entry of column 'A' to take todays date and preceeding entries take value progressively one day earlier, ie date minus 1, minus 2, minus 3, etc
d) column 'D'. latest value to be replaced with difference between and the previous value of that column('D')

OK . l'comprehend ?

Is it possible? can someone out there help.
would be immensely grateful

regards
biggles