| Securities registration | S-3 | 2000-08-15 | - |
| Quarterly report | 10-Q | 2000-08-11 | 2000-06-30 |
| NT 11-K | - | 2000-06-27 | 1999-12-31 |
| NT 11-K | - | 2000-06-27 | 1999-12-31 |
| Quarterly report | 10-Q | 2000-05-15 | 2000-03-31 |
| Proxy statement | DEF 14A | 2000-04-18 | 2000-05-19 |
| Annual report | 10-K | 2000-03-30 | 1999-12-31 |
| Passive ownership stake (update) | SC 13G/A | 2000-03-09 | - |
| Activist ownership stake (update) | SC 13D/A | 2000-02-29 | - |
| Passive ownership stake | SC 13G | 2000-02-15 | - |
| Passive ownership stake (update) | SC 13G/A | 2000-01-31 | - |
| Activist ownership stake (update) | SC 13D/A | 1999-12-14 | - |
| Quarterly report | 10-Q | 1999-11-15 | 1999-09-30 |
| Major company event | 8-K | 1999-11-03 | 1999-11-01 |
| 424B3 | - | 1999-09-17 | - |
| 424B3 | - | 1999-09-03 | - |
| Major company event | 8-K | 1999-09-02 | 1999-08-31 |
| Quarterly report | 10-Q | 1999-08-13 | 1999-06-30 |
| Major company event | 8-K | 1999-08-05 | 1999-08-02 |
| Passive ownership stake | SC 13G | 1999-08-05 | - |
| Activist ownership stake (update) | SC 13D/A | 1999-07-26 | - |
| 8-A12B | - | 1999-07-21 | - |
| Major company event | 8-K | 1999-07-01 | 1999-06-30 |
| 8-A12B/A | - | 1999-06-30 | - |
| Employee stock plan | S-8 | 1999-06-30 | - |
| Employee stock plan | S-8 | 1999-06-28 | - |
| Proxy materials | DEFA14A | 1999-06-02 | - |
| Proxy materials | DEFA14A | 1999-06-02 | - |
| S-4 | - | 1999-06-02 | - |
| Quarterly report (amended) | 10-Q/A | 1999-06-02 | 1999-03-31 |
| Annual report (amended) | 10-K/A | 1999-06-02 | 1998-12-31 |
| Quarterly report (amended) | 10-Q/A | 1999-05-18 | 1999-03-31 |
| Quarterly report | 10-Q | 1999-05-17 | 1999-03-31 |
| Annual report | 10-K | 1999-03-31 | 1998-12-31 |
| Insider trade | 4 | 1999-02-10 | 1999-01-31 |
| Activist ownership stake (update) | SC 13D/A | 1999-01-21 | - |
| Activist ownership stake (update) | SC 13D/A | 1999-01-12 | - |
| Activist ownership stake (update) | SC 13D/A | 1998-12-17 | - |
| Major company event | 8-K | 1998-11-24 | 1998-11-23 |
| Quarterly report | 10-Q | 1998-11-13 | 1998-09-30 |
| Major company event | 8-K | 1998-09-22 | 1998-07-14 |
| Activist ownership stake (update) | SC 13D/A | 1998-09-14 | - |
| Quarterly report | 10-Q | 1998-08-14 | 1998-06-30 |
| Prospectus supplement | 424B5 | 1998-07-13 | - |
| Activist ownership stake (update) | SC 13D/A | 1998-06-11 | - |
| Quarterly report | 10-Q | 1998-05-14 | 1998-03-31 |
| Major company event | 8-K | 1998-04-09 | 1998-03-16 |
| Proxy statement | DEF 14A | 1998-04-06 | 1998-05-06 |
| Annual report | 10-K | 1998-03-31 | 1997-12-31 |
| Prospectus supplement | 424B5 | 1998-03-13 | - |
