A DPU Yield chart displays yield levels of your processes over time and how the percentage of good units changes over time.
A DPU yield chart can only scale to 100%. When you draw a DPU Yield chart with improvement curve values that are greater than one (greater than 100%), the chart is scaled between 0 and 100% instead of being scaled to the data. Only the improvement curve portions that fall below 100% display on the chart. Unlike other DPU charts on which the improvement curve descends on the chart, the improvement curve on a DPU yield chart ascends.
Note: An improvement line does not display on any type of DPU chart that has data grouped by traceability or by shift, since these groupings are not based on time.
You will need to establish the starting date and DPM (defects per million) value for displaying the 10x improvement curve on DPU charts.
To change the Improvement Start Date and Improvement Start Value of a process from an open DPU chart:
Right-click the chart. Select Settings... from the menu that displays.
Then, change the values for these settings on the Settings tab of the Chart Settings dialog that opens.