| Quarterly report | 10-Q | 1997-08-12 | 1997-06-30 |
| Quarterly report | 10-Q | 1997-05-13 | 1997-03-31 |
| Proxy statement | DEF 14A | 1997-04-16 | 1997-05-21 |
| Annual report | 10-K | 1997-03-27 | 1996-12-31 |
| PRE 14A | - | 1997-03-27 | 1997-05-21 |
| Passive ownership stake (update) | SC 13G/A | 1997-02-14 | - |
| Passive ownership stake | SC 13G | 1997-02-12 | - |
| Passive ownership stake (update) | SC 13G/A | 1997-02-05 | - |
| Quarterly report | 10-Q | 1996-11-12 | 1996-09-30 |
| Employee stock plan | S-8 | 1996-10-04 | - |
| Quarterly report | 10-Q | 1996-08-12 | 1996-06-30 |
| 424B1 | - | 1996-06-21 | - |
| S-3/A | - | 1996-05-31 | - |
| Securities registration | S-3 | 1996-05-24 | - |
| Quarterly report | 10-Q | 1996-05-13 | 1996-03-31 |
| Proxy statement | DEF 14A | 1996-04-16 | 1996-05-15 |
| 10-K405 | - | 1996-03-28 | 1995-12-31 |
| Passive ownership stake (update) | SC 13G/A | 1996-02-21 | - |
| Passive ownership stake | SC 13G | 1996-02-07 | - |
| Passive ownership stake | SC 13G | 1996-01-25 | - |
| Quarterly report | 10-Q | 1995-11-13 | 1995-09-30 |
| Employee stock plan | S-8 | 1995-10-10 | - |
| Major company event (amended) | 8-K/A | 1995-10-05 | 1995-10-05 |
| Major company event | 8-K | 1995-09-15 | 1995-09-15 |
| Activist ownership stake (update) | SC 13D/A | 1995-08-21 | - |
| Quarterly report | 10-Q | 1995-08-11 | 1995-06-30 |
| Prospectus supplement | 424B2 | 1995-08-02 | - |
| Prospectus supplement | 424B2 | 1995-07-19 | - |
| S-3/A | - | 1995-07-18 | - |
| Securities registration | S-3 | 1995-06-16 | - |
| Activist ownership stake (update) | SC 13D/A | 1995-05-18 | - |
| Quarterly report | 10-Q | 1995-05-11 | 1995-03-31 |
| Proxy statement | DEF 14A | 1995-04-13 | 1995-05-17 |
| Annual report | 10-K | 1995-03-28 | 1994-12-31 |
| Passive ownership stake (update) | SC 13G/A | 1995-02-10 | - |
| Employee stock plan | S-8 | 1994-11-23 | - |
| Activist ownership stake (update) | SC 13D/A | 1994-11-16 | - |
| Quarterly report | 10-Q | 1994-11-09 | 1994-09-30 |
| Activist ownership stake (update) | SC 13D/A | 1994-10-27 | - |
| Activist ownership stake | SC 13D | 1994-10-26 | - |
| Quarterly report | 10-Q | 1994-08-11 | 1994-06-30 |
| Activist ownership stake (update) | SC 13D/A | 1994-07-19 | - |
| Activist ownership stake (update) | SC 13D/A | 1994-06-29 | - |
| Activist ownership stake | SC 13D | 1994-05-19 | - |
| Quarterly report | 10-Q | 1994-05-12 | 1994-03-31 |
| Proxy statement | DEF 14A | 1994-04-14 | 1994-05-18 |
| Annual report | 10-K | 1994-03-30 | 1993-12-31 |
| Activist ownership stake (update) | SC 13D/A | 1994-03-10 | - |
| Passive ownership stake (update) | SC 13G/A | 1994-02-14 | - |
| Activist ownership stake | SC 13D | 1994-02-08 | - |
