In the upper left corner of pareto chart, it will be marked: "O year × month (see the above picture)", representing the data acquisition period of this picture.

There are three main points:

1, and the bar chart represents the number of bad categories and the corresponding bad categories. Scratches rank first, 565,438+0 * *, followed by concave and convex surfaces, 36 * * *.

2. The line chart represents the cumulative percentage of each bad category. The number one scratch is 5 1 piece, accounting for 5 1% of the total number of defects (see "n = 134" at the top left of the figure). There are 36 concave-convex surfaces in the second place, which together with the first "scratch" is 87, accounting for 65% of the total number of defects 134, and so on.

3, pareto chart's main purpose is to find the main form of bad, the so-called 8: 2 principle. Taking the above figure as an example, the number of the first three failure forms accounts for 76% of the total defects. According to the quality management principle (8: 2), improvement can start from the first three failure forms, with clear objectives and easy operation.