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For obtaining the elapsed time for each Test Run, you may use the Test Runs Report. Then you may export it to CSV.
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In order to obtain the sum of the elapsed time, you may use the "Test Executions Report", which you can export to CSV if you wish to cross the values.
At
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Test Execution level, comparing the sum of the estimated times for each Test vs the sum of the logged time (work logs)
In this case we assume people log time on the Test Execution issues which we want to compare against the estimations made on the Test issues.
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