Hi,

Well for the control chart there are explanations here,
http://processtrends.com/pg_charts_control_chart.htm
http://peltiertech.com/Excel/Charts/RunChtLines.html

As for a particular formula to calculate the v-mask lines we would need
much more detail.

Cheers
Andy

JerryA wrote:
Del is correct about the v-mask. Its useful for determining if a process
change is neccesary. And yes, the lines are straight, and actualy come to a
point off the chart. If any results of the cusum show outside the lines, then
something has occured. I just was wondering if anyone knows the formula to
make it work on excel.

"JerryA" wrote:


Anyone know how to take a Cusum chart and plot a v-mask on it?

--

Andy Pope, Microsoft MVP - Excel
http://www.andypope.info