Come tax time ur account will pull up ur asx trading register from the asx....theres no hiding that.
So to confuse things if u hold ur shares longer than 12 months ul get a capital gains discount of 50% depending whot tax bracket u fall into as usual the more u earn the more tax u pay, the less u earn the less u pay.
If u make profit of 500k and have a 100k loss in the same year ul have a capital gains tax of 400k. Then ul get ur capital gains tax discount of 50% if u have held ur shares for 1 year and 1 whole day. U will be in the top tax bracket. Im not a account but ul pay around 100 to 150k tax for that financial year.