I have dates entered in cells A1 through H1, some of which are duplicate
dates and others which are unique dates.

What I need is a formula I can write in cell I1 which will tell me if the
date in cell A1 is unique in comparison to all the other dates in the range
A1 through H1.

I also need to extend this formula across cells J1 through P1 to repeat the
analysis for each of the respective dates in the data range. (i.e. I need
the formula in cell J1 to tell me if the date in cell B1 is unique in
comparison to all the other dates in the range A1 through H1).

Thanks for the assistance in advance!