Conditional Formatting -coloring of white is needed based on the previous cell value.

hi
I'm posting this as a separate thread because it is different than my previous question, although it will indirectly solve my previous problem!

I have a small problem.Can anybody please help me.

Please see the attachement to follow the problem.

Here for example in column D4,the entries are NST and STD

1)So i want it such that if first cell is NST, and 2nd cell is also NST and so on then the current cell(NST) which is same as the previous cell value
should be colored in WHITE using only Conditional Formatting and No macros.

So in the output(2nd screenshot) the 1st cell is NST and all other cells below that are in WHITE as it is same to its previous cell value hence they are in white.


2)Similarly I want it such that if first cell is STD, and 2nd cell is also STd and so on then the current cell(STd) which is same as the previous cell
should be colored in WHITE using only Conditional Formatting and No macros.

So in the output the 1st cell is STD and all other cells below that are in WHITE as it is same to its previous cell value hence they are in WHITE.

The Conditional Formatting for NST and STD cases should be dynamic,should be applied for whole(entire) column.


Thank You.