It's not possible through the UI, I'm afraid. If it's a one-off, we could extract the data from the database and send it to you.
An alternative is to save the time explicitly, although it's going to be relative to some starting point. Like this:
>> startTime = calendar::now
*question: How quickly can you answer?
>> q1Time = calendar::now
>> q1Delay = q1Time - startTime
q1Delay would show up in the CSV as ‘2.056 seconds’, for example.