Hey guys -

I have an easy question which I'm definitely overcomplicating. I have the following data:
A B C D
2/12/1962 70.46 8.18 -1
2/13/1962 70.45 8.10 -1
2/14/1962 70.42 8.15 1
2/15/1962 70.74 8.85 -1
2/16/1962 70.59 9.06 0
2/19/1962 70.41 8.48 0
2/20/1962 70.66 8.25 0
2/21/1962 70.32 6.95 0
2/23/1962 70.16 5.75 0

I want to create a formula in E1 which basically says, take whatever is in D1 (i.e. 1 or -1 and continue down for the next three 3 cells with that value unless D changes to something new in which case continue what the former value for the next three cells

As an example, the values for E would become:
E
-1
-1
1
-1 (basically the -1 would continue for the next three cells)
-1
-1
0
0
0
0

Many Thanks All,

-L