IBX Chart, page-162

Thanks Lackflash50.
But I'll simplify it for both of you: generally as follows-
Add up all your total share price/s purchases - then deduct from your total purchases, any Cali liquidator/trustee's letter that says your shares have now been assessed as Zero value.
Then deduct your purchase price from Zero.
And that's your tax capital loss amount for your tax return.
Naturally, subject to offsets on your prior year's losses/gains.
However, it is imperative that do your own research. Do not rely on my rant.

Cheers.
Stretguy.