Stunningly surprised

I bought artis at 5.75 on March 8 and yesterday it closed at 7.86 add $0.18/unit of distributions in that time. I suppose this should be pleasantly surprised, though it is puzzling. I hate sudden large and unexplained price changes. Mainly because they show that prices aren't rational and it forces me to question my ability to predict things. Granted, my decisions regarding SFK pulp and Nortel outright told me that I suck. When I don't see an apparent trigger for something like this, I worry that it won't last.