XPS 15 9510 Sleep Current too high

I've had my XPS 15 9510 for a few months now, and have been overall fairly happy with it (besides the super slow wakeup time, which I'll post in another thread).

However, one problem seems to plague it.  For some reason, it has a rather substantial current drain when sleeping.  The computer runs about the right amount of time (most of an 8 hour workday, and obviously depending on conditions).  But the battery drain when it should be sleeping is pretty significant.  I've regularly opened it up several hours after closing it to find it mostly drained.  This last time, I put it away Friday 5PM with a full charge, and when I opened it up Monday at 10AM, it was completely depleted. Enough so that it prevented Windows from restoring correctly. 

Is this normal for this laptop? (all my prior laptops, Dell or otherwise, have had sleep times closer to a week or longer.)

Is there a setting I can tweak that will fix this?