It is an amount that I do not think its too low for only a 10$ variation. Probably it will get more stable as more and more people enter into trading Bitcoin, but thinking that there are not so many people doing it, it does not seem strange.
It depends on the market depth. The volume of bitcoin is quite low recently. I think there will be big rise soon.
the only reason for the recent low volume is that the day traders has stopped (or slowed down) their daily process of buying and selling because of the stable price.
you can conclude from that a price rise.
But the daily price change is still around 2 to 3 percent. If they use margin, they can still make some profits.