poolstat not showing "used" figures after upgrading to 0.5.11-0.175.3.1.0.5.0

After updating the O/S to 0.5.11-0.175.3.1.0.5.0, and rebooting, the "poolstat" command consistently shows 0.0 in the "used" column. Before, it gave actual figures, more or less correllated to the "load" figures. Would this be a bug in the new release, or would anything be broken by the reboot?

<span style="font-family: courier new,courier;">  pset</span><br/><span style="font-family: courier new,courier;">id pool size used load</span><br/><span style="font-family: courier new,courier;"> 5 xxxx1 2 0.00 0.07</span><br/><span style="font-family: courier new,courier;"> 4 xxxx2 44 0.00 1.05</span><br/><span style="font-family: courier new,courier;"> 1 xxxx3 8 0.00 0.06</span><br/><span style="font-family: courier new,courier;"> 0 pool_default 12 0.00 0.33</span><br/><span style="font-family: courier new,courier;"> 3 xxxx5 18 0.00 0.15</span><br/><span style="font-family: courier new,courier;"> 2 xxxx6 12 0.00 0.64</span>