Gas consumption varies depending on the dive profile and diver skill. The minimum consumption is by a diver who uses the correct amount to neutralize buoyancy and does not waste gas by overfilling, or by excessive weighting. The actual volume of the bladder should not affect gas consumption by a skilled user, as only enough gas to achieve neutral buoyancy is needed. Deep dives will require more gas, and dives in which the diver ascends and descends by large amounts and/or frequently, will require venting for each ascent and inflation for each descent. The amount of gas used during the dive during US Navy trials was generally below 6% of the total gas consumption, and the use of small dedicated cylinders for inflation was considered adequate, but not necessary.