LeBron James had a usage percentage of 31.3 in 2015-16.

cavilers players usage rate without lebron james 2016
NAMESEASONTMGPUSG%MPGPPGRPGAPGSPGBPGTPGFGMFGAFG%3PM3PA3P%FTMFTAFT%MINPTSREBASTSTLBLKTOVPF+/-
LeBron JamesLeBron James2015-16CLECLE7631.335.625.37.46.81.40.63.39.718.652.01.13.730.94.76.573.12,7091,92056551410449249143+618
StatMuse has season-level data for usage percentage going back to the 1977-78 season.