So how do you factor in the 50% after 12 months discount? you're...

So how do you factor in the 50% after 12 months discount? you're saying it's 19k instead of 20k but why?

I've been told if I don't have any income and I can sell up to 36k worth of profit in shares ive held for 12 months and I won't have to pay any tax because 36/2=18k and tax free income up to 18k?

Also if your broker has your taxfile number can't the ato see all your transactions and buy sell dates etc therefore be able to calculate it for you?