EWMA Chart in Excel

Use the EWMA Chart when you have one sample and want to detect small shifts in performance.

The EWMA (exponentially weighted moving average) chart's performance is similar to the Cusum chart.

Example of an EWMA Chart created in QI Macros for Excel

EWMA chart in Excel

To create an EWMA control chart using QI Macros:

  1. Highlight your data and select "EWMA" from the "Control Charts (SPC)" drop-down menu.
  2. Next you will be prompted to either accept the default alpha parameter of 0.2 or enter in your own:
  3. ewma chart prompt

 

Note: Per Montgomery 4th Edition, “values of λ in the interval 0.05 ≤ λ ≤ work well in practice, with λ = 0.05, λ = 0.10, and λ = 0.20 being popular choices. A good rule of thumb is to use smaller values of λ to detect smaller shifts."
The lower the value of the alpha parameter, the closer your UCL and LCL will be to the CL; and vice versa.

 

Learn More...


Why Choose QI Macros Over Other Control Chart Software?

affordable

Affordable

  • Only $249 USD - less with quantity discounts
  • No annual subscription fees
  • Free technical support

easy to use

Easy to Use

  • Works right in Excel
  • Create a chart in seconds
  • Easy to customize & share charts

proven and trusted

Proven and Trusted

  • More than 100,000 users
  • In More than 80 countries
  • Five Star CNET Rating - Virus free