Number Nonconforming (np) Chart
This spreadsheet is designed for up to 50 samples. Enter data ONLY in yellow-shaded cells.
Each sample must have a constant sample size; enter this in cell C6.
Click on the sheet tab to display the control chart (some rescaling may be needed).
Sample size 100
Average (np-bar)
Standard deviation
Number
Sample Nonconforming LCLnp CL UCLnp
1 3 0 2.2 6.6005
2 1 0 2.2 6.6005
14 3 0 2.2 6.6005
15 4 0 2.2 6.6005
16 1 0 2.2 6.6005
17 1 0 2.2 6.6005
18 2 0 2.2 6.6005
19 5 0 2.2 6.6005
20 2 0 2.2 6.6005
24 0 0 2.2 6.6005
25 1 0 2.2 6.6005
26 #N/A #N/A #N/A
27 #N/A #N/A #N/A
28 #N/A #N/A #N/A
39 #N/A #N/A #N/A
40 #N/A #N/A #N/A
2.2
1.466833324
41 #N/A #N/A #N/A
42 #N/A #N/A #N/A
0
1
2
3
4
5
6
7
1 3 5 7 9 11 13 15 17 19 21 23 25 27 29 31 33 35 37 39 41 43 45 47 49
Number nonconforming
Sample number
Number nonconforming (np) chart Number nonconforming
Lower control limit
Upper control limit
Center line