I think the most value from this type of data is to make comparison with other detectors.  I do not have any other to measure now.  But in as much as you asked I went to the Duracell site and looked at the AA ULTRA and Copper Top batteries.  By using the average of the average currents over the usable voltage range and assuming I had 10 batteries in series so I could use the batteries down to 1.1 volts I get between 9 and 13 hours of life.  In actual use I get better than that more like 20+ hours.  The reason for the difference may be the unit draws less power when it is not searching for the bottom like it is hanging up side down in my garage and I use the batteries to a lower level than 1.1 volts.