Bloomberg might incorporate US and Deutchland exchanges as well. I used today's Google Finance for CVE:PTK. Bloomberg has really nice offices on Park Ave. I try not to argue too much with people who have nice offices.
I provided these as examples that I had calculated. I did the 30 trading days just now, and provided the whole input dataset so people could see how it works. I'd encourage everyone to calculate their own, using their own intervals - with the proviso that nothing that I say is to be construed as financial advice. It's just layperson's perspective, but it has the advantage of minimizing the effect of wild swings on thin volume, which are notoriously hard to detect if your eyes are glued to a flippin' screen.
