Hi Bubbly,
My understanding is that the ASX 200 index live price is what is actually occurring in the market, The ASX 200 cfd price closely mirrors this price but it is more of a function of supply and demand with IG traders at the time. If traders are caught in either a long or short squeeze then often the cfd price is stretched compared to the market index. Remember that we are taking a position on whether the ASX 200 price will rise or fall...we don't actually own the underlying asset. Hope that helps...do you mainly trade the ASX 200 cash?
Regards, Johnno