I have a percentage for each issue and when i want to see percentage per project and month it shows me the sum of percentages instead of average
The calculation depends on the formula used and the context of report. If the percent is calculated on the issue level, possibly you need to divide the whole thing with, e.g., Issues created. On each issue level, it would divide by 1, while on Project and Time level, it would give an average for issues created in the context.
If this was not what you are looking for, please let me know what formula you use for calculating the percentage.
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