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number of non drive alone commute trips = Non Drive Alone Trip (NDAT) rate 
total number of potential commute trips


Joe works five days a week and drives alone on three of those days. Joe's drive alone rate can be calculated as follows:

2 (number of non drive alone commute trips) = 40% (Non Drive Alone Trips)
5 (total number of potential commute trips)

If your response rate is below 70% the difference between your rate and 70% will be "filled-in" with drive alone trips. This will hurt your survey results and may mean that your company does not meet its CTR targets.

Steps to Surveying

Determine when you survey. You can contact your ETR to find out the survey schedule for your site. Usually you will be notified at least 45 days in advance of your survey period. If you need an extension on the timing of your survey, please send a written request.

  1. Determine whom you will survey.
  2. Select your survey method from the online or paper format.
  3. Complete and return a Survey Response Form.
  4. Distribute survey instrument to employees.
  5. Collect completed surveys from employees. There is a required 70% response rate on the state-provided survey.
  6. To close out an online survey, email Greg King at To return paper surveys, email for courier pick-up. Reveiw the Paper Survey Pick-up Instructions (20KB MS Word) for additional information. Remember to complete your Employer ID sheet and include it with your surveys.
  7. Review your survey results report when it is sent to you.