This year AP rates have generally run about 30% off of the rack rate for the current season when you go. And like MauraAndIainsDad said, some codes have been better.
My last 3 stays as an annual passholder have been made with codes versus AP rates. I realize that may not ALWAYS be the case, but sure was for me this year.
Of the deluxes we checked for our January '02 trip, most of the AP rates were only $5 cheaper than the code rates, but at AKL, the sv rooms were $20 cheaper with the AP rate.