I have two columns one called Start Date and another called End Date.

The formula in the cells under Start is as follows:

=IF(F12>=1, $F$9, IF(G12>=1, $F$9+1, IF(H12>=1, $F$9+2, IF(I12>=1, $F$9+3, IF(J12>=1, $F$9+4)))))

Forluma in the cells under End Date is:

=IF(F12>=2, F9, IF(G12>=2, F9+1, IF(H12>=2, F9+2, IF(I12>=2, F9+3, IF(J12>=2, F9+4)))))

The cell F9 is a date and is the first day of a week i.e 16/6/2008.

F12 to J12 has been formatted using coditional formatting so that if a 1 or 2 is inputed into the cell it changes colour and highlights the days when construction work is being carried out on. The idea is 1 is the start date all the other days are 1 as well but the last day that work is carried out on i would input 2 and that would go straight into the end date cell.

This only works for one week. I have a 36 week programme. I have tried the formlua.....IF(F12:Z12>=1, F9) but that doesn't work.

Any ideas?