Wire Parameters_Percentage Offset_Along a Path

Hi

I have a simple curved path drawn up in 3DS max 9.

I have attached a DUMMY using Path Constrains, called (dummy 1)

(dummy 1) sits at 0% along the path

I have attached another DUMMY to the same path using Path Constrains, called (Dummy 2)

(dummy 2) sits at 20% along the path

Both dummy’s are set to Follow the path

I am trying to wire (dummy 1) to (dummy 2) so when I key frame (dummy 1), (dummy 2) will always be offset the same amount from (dummy 1)

So I’m looking for an expression to put into Wire Parameters for (dummy 2) to keep it the same distance from (dummy 1)

Can anyone help?

Kind regards
Roger :)