This is completely correct... asx300 rebalances in March and September with only share count changes implemented at the June and December rebalances. Institutions follow the asx300 much more often than the 200, so the December rebalance has somewhat lower trading activity than March and September.
You can expect to see a step change in the gross short sales of CU6 as the futures contract is based on the 200. Index arb trades that facilitate futures trading rely on the ability to short the index constituents. It doesn't mean anything material for prices other than improving liquidity/lowering spreads, just something to be aware of.
CU6 Price at posting:
$4.55 Sentiment: None Disclosure: Not Held
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