Values in the result page and the video are mismatching

I am running a test on webpage test (on the private instance) and creating its video and after that down downloading the same video, but I see there is a variance in the result page time and time showing in the video.

Please refer the screenshot attached.
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If you can see the summary page took almost 2.5 seconds but in the video, it is showing 1.4 seconds. Not able to correlate it.