In this Excel tutorial you will teach yourself how to create a chart with upper and lower control limits.
Let's begin from preparing data table.
Highlight data table. Go to the ribbon to the Insert tab. Choose a Line chart.
Your chart should like similar to this one.
Right click first lower limit line and choose Format Data Series from the menu.
Change line color to red and set width to 5 pts.
Do the same for upper limit line. Change chart title. Your chart is ready.