alley,
I do not know whether you have noticed or not, but there is a high correlation between OZL and PNA in the ratio of 1 OZL to 2 PNA.
Watch it over a number of weeks and notice how both share prices seem to move back to this ratio every time they start to depart.
I don't think there is anything significant to it. It is just something to bear in mind and watch.
HT1