I've just read this document titled "ASX SPI 200® Futures" by the ASX
www dot asx dot com dot au/products/pdf/asx_spi_200_futures.pdf
I apologise for the combobulated URL but because I'm a n00b (2 posts) I'm not allowed to post links :p
Refer to the chart on page two titled "ASX SPI 200® Futures Volume & Open InterestJan 2004 – April 2010". Notice that the volume is significantly higher in the last month of the quarter. I'm curious as to why this might be.
I'm not a trader. I'm just edgeucating myself at this stage.