I am designing a measurement spreadsheet with the
following conditions:

DESCRIPTION:
For a Project, every Milestone is linked to another
milestone.

If Linking milestone 'ML' was completed on time, then
check if this Milestone was completed on time too by
comparing the number of days 'N' and the estimated number
of days for Milestone 'E'.

N= E "On Time"
N E "Over Time"
N < E "Under Time"

SO IT WOULD BE SOMETHING LIKE

FOR SAME PROJECT NUMBER
IF ML (Actual Date of Completion) = ML (Estimated Date of
completion )

THEN

COMPARE N and E

N= E "On Time"
N E "Over Time"
N < E "Under Time"

Thanks in advance.
Ken