The formula i have entered does not work for all conditions. Here is the
formula i have entered and works for 2 conditions but not all 4.

=IF(A12=0,"",IF(S12=0,"",IF(s12<=R12,"GREEN",IF(S1 2R12,"RED/LATE",IF(R12<=TODAY()+3,"YELLOW","WHITR")))))

A12, R12, S12 contain dates and Column T is a status column. If no date is
in column A then i want column T to be blank. And if column S date is blank,
then i want column T to be white (on target for due date, column R), or
yellow (3 days before due date). If column S is R it should be RED/LATE,
or if < should be GREEN. The red and green work fine, but i can not get the
yellow or white to work. What can i do?