This is the number of respondents who have Taken the survey. Click on that number to see individual email addresses that have Taken the survey.
How the queue system works?
When you send the survey email, initially all the email addresses are put in the Queued column. The engine picks up the email addresses from this queue and delivers them. When the delivery is complete the email addresses are moved to the Sent column (the move from the Queued column to the Sent column should take just a couple of minutes).
Suppose you send the survey email to a group containing 5 email addresses. Initially the count under the Sent column will be 5 Now suppose 2 of the respondents View the survey, then the count under the Sent column will decrease by 2 and the count under he Viewed column will increase by 2.
So now, the Sent queue will contain 3 email addresses (i.e. 5 total sent minus 2 viewed). The Viewed queue will contain 2 email addresses.
The numbers in the various queues will keep changing as respondents submit the survey. However, when the numbers across all columns (i.e. Queued, Sent, Viewed, Taken) for a particular group, are added, they should equal the number in Count column.