[lxc-users] interpreting lxc-top CPU numbers

[Chris Burroughs]

Container            CPU      CPU      CPU      BlkIO        Mem
Name                Used      Sys     User      Total       Used
c3                242.85    71.47   193.44    2.92 GB   48.33 MB
c4               2028.90   209.47  2054.37  588.00 KB  103.82 MB
n2                  1.23     0.12     0.19    4.00 KB    2.24 MB
TOTAL (3 )       2272.98   281.06  2248.00    2.92 GB  154.40 MB

What are the units on the CPU columns?  They don't appear to be either a 
relative or absolute percent.