You can save process capability indices in an OUTLIMITS= data set if you provide specification limits with the LSL= and USL= options. This is illustrated by the following statements:

title 'Control Limits and Capability Indices'; proc shewhart data=Partgaps; xchart Partgap*Sample / outlimits = Gaplim2 usl = 270 lsl = 240 nochart; run;

The data set `Gaplim22`

is listed in Output 17.37.1.

Output 17.37.1: Data Set `Gaplim2`

Containing Control Limit Information

Control Limits with Capability Indices for Gap Width Measurements |

_VAR_ | _SUBGRP_ | _TYPE_ | _LIMITN_ | _ALPHA_ | _SIGMAS_ | _LCLX_ | _MEAN_ | _UCLX_ | _LCLR_ | _R_ | _UCLR_ | _STDDEV_ | _LSL_ | _USL_ | _CP_ | _CPL_ | _CPU_ | _CPK_ |
---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|

Partgap | Sample | ESTIMATE | 5 | .002699796 | 3 | 242.087 | 259.667 | 277.246 | 0 | 30.4762 | 64.4419 | 13.1028 | 240 | 270 | 0.38160 | 0.50032 | 0.26288 | 0.26288 |

The variables `_CP_`

, `_CPL_`

, `_CPU_`

, and `_CPK_`

contain the process capability indices. It is reasonable to compute capability indices in this case, since Figure 17.96 indicates that the process is in statistical control. For more information, see the section OUTLIMITS= Data Set.