Continuous Measurement. Answers to some of your most common questions

The Fall 2019 Numeris radio survey was the first step in transitioning to continuous measurement in diary markets. Since the release of this survey we’ve had many questions from Radius users about what this means and how it affects them. We’ve compiled some of the most commonly asked questions to help you.

1. Why did the methodology for diary markets change?

There were several reasons, including improved recruitment of participants, more stable data and more frequent measurement. For details visit

2. How are survey releases affected?

All diary markets will now be measured twice a year – Spring and Fall. Full coverage will now be available in both surveys.

3. Can I still use two-book averages for buying/selling radio?

It is not recommended. The Fall 2019 is comprised of 50% sample from the previous survey (Spring 2019 or Fall 2018, depending on the market’s survey frequency), along with 50% new sample. Using a two-book average would mean that some respondents would be included twice. In order to use survey averaging you would have to use a previous unduplicated survey (eg. Fall 2018/19 for markets measured in Spring/Fall or Fall 2017/19 for Fall only markets).

4. Is the Fall 2019 survey the same as a two-book average?

No. Only some of the sample from the previous survey was used in Fall 2019.

5. Can I breakdown the Fall 2019 survey into the two surveys?

No, it is not possible to look at the two components of the survey data separately.

6. Will diary markets be measured every week like meter markets?

No. Diary markets will have a total 24 weeks of measurement of a year. A market will be measured every second week. There is no measurement during December.

7. What will happen for the Spring 2020 release?

Continuous measurement will be fully implemented. The survey will be comprised of six weeks of data from Fall 2019 and 12 weeks of Spring 2020 data.

8. Has my Radius software changed to accommodate continuous measurement?

No changes to Radius were required.

9. Will monthly or weekly data be available?

At the moment Numeris is offering only twice a year releases.

For more information please feel free to contact us at