Conditional Formatting - formula for adjacent cells

Hi!, I am trying to drag a conditional formatting but I haven't been able to do it.

 

I actually need to hide the value in the column T if the value in Tx is the same to the previous value in the same column, ie, I want to format the font in white with white fill if the value in Tx is the same to the value in T(x-1) and used from T4 to T700.

However, When I write the equation and I define the range, the same equation is applied for the hole range and it doesn't change when I move down.

Per example if I define the format if T5=T4, then I drag it down and In the cell T100, it still answer to the condition T5=T4, I want the value in T100 to answer to the condition T100=T99.

Can anyone help me?

Thanks!