Excel Histogram with Cp, Cpk, Pp, Ppk
Just Drop Your Data into this Excel Template
This Histogram template in Excel allows you to input - USL, LSL and your data
Calculates - Mean, Median, Mode, Cp, Cpk, Pp, Ppk, Cpm, Stnd Dev, Max, Min, Z bench, Cpk Upper, Cpk Lower, Z target, % defects, PPM, Expected, Normal Distribution curve.
For more information on the formulas used in this Excel histogram template see the QI Macros formulas page.
Why Use a Histogram?
Use an Excel histogram to determine the distribution of measurable data and the capability (i.e., the level of performance the customers can consistently expect) of the process.
What do Histograms Show?
Histograms show the spread, or dispersion, of data. The Excel histogram uses variable data to determine process capability. The customer's upper specification (USL) and lower specification limits (LSL) determine process capability. With attribute data (i.e., defects), capability assumes that the process must deliver zero defects.
Cp and Cpk for Process Capability Analysis
Cp>1 Process is capable (products fall between the customer's upper and lower specification limits), and between 3-4 sigma (Cp=1.0 to -1.33)
Cpk>1 Process is capable and centered between the LSL and USL, not shifted either direction.