Chart Question

[Mike]

I have a statistical process control chart with upper and lower control
limits identified by a dotted line. Control limits are calculated based on a
certain amount of deviation from the mean. After 7 data points, a new mean
is calculated based on the next 7 data points and therefore new control
limits. The true way to illustrate this is to have a break in the dotted
control limit lines on the chart, but Excel slopes the line to the new
control limits. Is there a way to have a break between these control limit
lines? 3 sets of 7 data points are on the chart.

 

[smartin]

I have a statistical process control chart with upper and lower control
limits identified by a dotted line. Control limits are calculated based on a
certain amount of deviation from the mean. After 7 data points, a new mean
is calculated based on the next 7 data points and therefore new control
limits. The true way to illustrate this is to have a break in the dotted
control limit lines on the chart, but Excel slopes the line to the new
control limits. Is there a way to have a break between these control limit
lines? 3 sets of 7 data points are on the chart.

Try breaking up the readings into separate columns so they can be
treated as individual series. Something like this:

Reading# Series1 Series2
1 X
2 X
3 X
4 X
5 X
6 X
7 X
8 X
9 X
10 X
11 X
12 X
13 X
14 X
....

 

[Herbert Seidenberg]

Excel 2007, X Y Chart
Conversion to step chart.
Dynamic limit lines.
http://www.mediafire.com/file/2aimjlmjrhy/10_16_09a.xlsx

 

[Jon Peltier]

Try this:

Step Charts in Microsoft Excel
http://peltiertech.com/Excel/ChartsHowTo/StepChart.html

Line Chart vs. Step Chart
http://peltiertech.com/WordPress/line-chart-vs-step-chart/

- Jon