Think about what is being done.
This problem is an interesting one. If you think about what you are doing it all makes very clear sense.
By selecting the range A2:A35 and comparing A2 to A3, you are saying, "if I am the same as the value below me, I am not unique." This means that the last value is considered the unique value.
By selecting the range A3:A35 and comparing A2 to A3, you are saying, "If I am the same as the value above me, I am not unique." Now, the first value is going to be considered the unique value.
However in this example, your range doesn't include the entire dataset. You'll notice that the first "Actuaries" is not highlighted and it should be. Since the 1st row is a header row, it should be different from the data so you can do the comparison to the first row, and still select the range of A2:A35 so the complete dataset is included. Now the first "Actuaries" will be highlighted as well.
