If you short 1 standard XJO contract, you're guaranteed to lose...

If you short 1 standard XJO contract, you're guaranteed to lose $25 x 20.9 =~ $525 for dividend adjustment. If you're long XJO you'll get paid that amount. You'll also have to pay the long/short interest.

Let's say the index is 5250 at 16:00:00, after dividend adjustment the index will drop to 5229.1 at 16:00:00. Usually games get played during the 10 minute auction.

If you're not familiar how this works, stay away and watch a few games before you decide to play it right.

NAB and ANZ go ex-div Monday. They are around 10.3% of the index