. o = Range/DZ ; (All 4 companies have sample size = 30, therefore D2= 4.0855 using chart value) Company UCL LCL USL LSL Mean 30 Process Process capability capable index (Yes/No) 1.5691 1.5535 1.62 1.5 1.564 0.3522 1.59 Yes 3.3051 2.8665 5 0 3.18 1.026 1.77 Yes 0.365 0.315 0.38 0.32 0.354 0.1174 0.044 No 33.87 31.2763 35 32 32.67 1.175 0.57 No