| Variable | Year | Supplement |
|---|---|---|
| EXCHANGE | 2020 | In both sample adult and child questionnaires |
| EXCHANGE | 2019 | In both sample adult and child questionnaires |
| EXCHANGE | 2018 | Person (core questionnaire) |
| EXCHANGE | 2017 | Person (core questionnaire) |
| EXCHANGE | 2016 | Person (core questionnaire) |
| EXCHANGE | 2015 | Person (core questionnaire) |
| EXCHANGE | 2014 | Person (core questionnaire) |