Need the drop down to go through different scenarios by pressing F9

[198four]

Guys need your brilliance again.

See the attached excel and the red text. Basically i am trying to see if there is a way that a certain cell can go through 1-3 values automatically.

[FDibbins]

Short answer - without using VBA, no

There is nothing magical about a drop down (data validation), it acts in the exact same way as if you had entered the data manually, and excel formulas only see the data in the cell as if it had been entered manually.

Also, you have a circular reference error in your file. This is where a cell uses itself in a formula in that cell.
You have a whole range that says...
R16=IF($G$5=1,R6,R16)

Not sure what you are trying to do there, but circ ref errors can give all sorts of unexpected results - best to avoid if possible