Even distribution allows your team to receive a constant data flow throughout your desired recurrence period of 30, 60, 90, 180, or 365 days. When enabled, a 14-day eligibility window is automatically assigned within the recurrence period for each user to view a survey. This eligibility window has the following characteristics:
- The start day of the eligibility window is constant inside the recurrence period. For instance, if the eligibility window starts on day three of a 30-day recurrence period, then the next time the user is eligible for an NPS survey is day 33 after an NPS survey was published, day 63, day 93, and so on.
- If the eligibility window doesn't fit into the current recurrence period, it continues into the next one. For instance, if the recurrence period is 90 days and a user's eligibility for a survey starts on day 88, the user is eligible for the survey for the last two days of the current recurrence period and another 12 days of the following one.
- When an NPS survey is published, we calculate the eligibility of the visitors as if there was another recurrence period before the current one. As in the previous example, all the visitors whose eligibility window would start 13 days before the Publish day would be eligible for the survey.
Example Scenario
How many visitors will see the NPS survey with the following settings:
- Even distribution is enabled.
- Recurrence is set to every 90 days.
- Currently there are 10,800 eligible visitors and 100 percent of them log in every single day.
After even distribution is enabled for your NPS survey, Pendo assigns each visitor a 14-day eligibility window when the user can see it. What happens on the 1st day?
- On the first day of your 90-day recurrence period, approximately 120 people of your targeted segment are eligible to see the survey (1.2 percent).
- However, all visitors whose eligibility window starts on days 77 through 90 also become eligible on day one.
- So, approximately 14 * 1.2% = 16.8% (~1814 visitors) of the visitors are eligible to see the survey on day one.
Then, approximately 1.2 percent of visitors in the segment become eligible each subsequent day.
This approach evenly distributes visitor eligibility windows across the recurrence period, ensuring a steady data flow throughout.
You can enable even distribution at any time in the Schedule tile in the survey's Settings page when editing your existing survey. For more information, see Set up an NPS survey. If you’ve already published your NPS survey, Pendo recalculates it in the background to help smooth out visitors who haven’t seen your survey yet.
Email backup
You can configure an NPS survey with an email backup. In this case, even distribution is required. The backup email is sent to the user after the eligibility window of 14 days if the user didn't log in to the application and didn't view the NPS survey.
Because of the cyclical nature of the eligibility window, some visitors might receive NPS backup emails shortly after the NPS survey is set to Public, if they didn't interact with the NPS survey in-app. For example, if the recurrence period is 90 days and a user's eligibility for a survey starts on day 78, the user is eligible for the survey only for the first 2 days after a survey was published. If the user didn't interact with the NPS survey in-app, a backup is sent by Pendo.