| Form type | Document | Filing | Description | Filing date | Reporting date | File number(s) |
|---|---|---|---|---|---|---|
| 4 | Open Document | Open Filing | OWNERSHIP DOCUMENT | Feb 23, 2022 | Feb 18, 2022 | 000-22345 |
| 4 | Open Document | Open Filing | OWNERSHIP DOCUMENT | Feb 4, 2020 | Feb 3, 2020 | 000-22345 |
| 4 | Open Document | Open Filing | OWNERSHIP DOCUMENT | Feb 12, 2019 | Feb 8, 2019 | 000-22345 |
| 4 | Open Document | Open Filing | OWNERSHIP DOCUMENT | Feb 14, 2018 | Feb 12, 2018 | 000-22345 |
| 4 | Open Document | Open Filing | OWNERSHIP DOCUMENT | Feb 8, 2017 | Feb 6, 2017 | 000-22345 |
| 4 | Open Document | Open Filing | OWNERSHIP DOCUMENT | Feb 23, 2016 | Feb 19, 2016 | 000-22345 |
| 4 | Open Document | Open Filing | OWNERSHIP DOCUMENT | Jun 10, 2015 | Jun 10, 2015 | 000-22345 |
| 4 | Open Document | Open Filing | OWNERSHIP DOCUMENT | May 21, 2015 | May 20, 2015 | 000-22345 |
| 3 | Open Document | Open Filing | OWNERSHIP DOCUMENT | Mar 17, 2015 | Mar 13, 2015 | 000-22345 |