The count is the number of observations for each defect. The height of the bars of the histogram represents the count of each category, which is shown on the left Y-axis.
Percent is the percentage of observations for each defect. Percent is calculated by (count for type of defect/total number of defects) x 100. The height of the bars of the histogram represents the percentage of each category, which is shown on the right Y-axis.
The cumulative percentage (Cum %) is the percentage of occurrences of any given value added to the percentage of occurrences for all preceding values. The blue line represents the cumulative percentage and can help you assess the added contribution of each category.