| Major company event | 8-K | 1999-01-15 | 1998-12-31 |
| Major company event | 8-K | 1999-01-13 | 1999-01-13 |
| Passive ownership stake (update) | SC 13G/A | 1999-01-07 | - |
| Major company event | 8-K | 1998-12-30 | 1998-12-30 |
| 424B3 | - | 1998-12-30 | - |
| Major company event | 8-K | 1998-12-21 | 1998-11-30 |
| 8-A12G | - | 1998-12-21 | - |
| S-3/A | - | 1998-12-16 | - |
| POS AM | - | 1998-12-10 | - |
| Securities registration | S-3 | 1998-11-25 | - |
| Major company event | 8-K | 1998-11-24 | 1998-11-24 |
| Quarterly report | 10-Q | 1998-11-10 | 1998-09-26 |
| Passive ownership stake (update) | SC 13G/A | 1998-09-18 | - |
| Passive ownership stake (update) | SC 13G/A | 1998-09-10 | - |
| Quarterly report | 10-Q | 1998-08-11 | 1998-06-27 |
| S-3/A | - | 1998-08-05 | - |
| Securities registration | S-3 | 1998-07-24 | - |
| Quarterly report | 10-Q | 1998-05-12 | 1998-03-28 |
| POS AM | - | 1998-05-04 | - |
| S-3/A | - | 1998-04-30 | - |
| 10-K405/A | - | 1998-04-24 | 1997-12-27 |
| Securities registration | S-3 | 1998-04-22 | - |
| Proxy statement | DEF 14A | 1998-04-20 | 1998-05-27 |
| PRE 14A | - | 1998-04-10 | 1998-05-27 |
| 10KSB40 | - | 1998-03-27 | 1997-12-27 |
| POS AM | - | 1998-03-12 | - |
| Passive ownership stake | SC 13G | 1998-03-05 | - |
| 424B3 | - | 1998-03-03 | - |
| Passive ownership stake (update) | SC 13G/A | 1998-02-17 | - |
| Passive ownership stake (update) | SC 13G/A | 1998-02-17 | - |
| Passive ownership stake (update) | SC 13G/A | 1998-02-17 | - |
| Passive ownership stake (update) | SC 13G/A | 1998-02-17 | - |
| Passive ownership stake (update) | SC 13G/A | 1998-02-17 | - |
| Passive ownership stake (update) | SC 13G/A | 1998-02-17 | - |
| Passive ownership stake (update) | SC 13G/A | 1998-02-17 | - |
| Passive ownership stake (update) | SC 13G/A | 1998-02-11 | - |
| Major company event (amended) | 8-K/A | 1998-01-26 | 1997-11-12 |
| Passive ownership stake | SC 13G | 1998-01-21 | - |
| 424B3 | - | 1997-12-30 | - |
| Major company event | 8-K | 1997-11-26 | 1997-11-12 |
| Major company event | 8-K | 1997-11-26 | 1997-11-12 |
| Quarterly report | 10-Q | 1997-11-12 | 1997-09-27 |
| Employee stock plan | S-8 | 1997-11-10 | - |
| S-3/A | - | 1997-11-10 | - |
| Securities registration | S-3 | 1997-11-04 | - |
| Proxy materials | DEFA14A | 1997-10-29 | - |
| Proxy materials | DEFA14A | 1997-10-10 | - |
| DEFM14A | - | 1997-09-22 | - |
| S-4 | - | 1997-09-22 | - |
| Activist ownership stake | SC 13D | 1997-09-04 | - |
