| Securities registration | S-3 | 1999-03-03 | - |
| Passive ownership stake (update) | SC 13G/A | 1999-02-16 | - |
| Passive ownership stake (update) | SC 13G/A | 1999-02-12 | - |
| Passive ownership stake (update) | SC 13G/A | 1999-02-11 | - |
| Passive ownership stake (update) | SC 13G/A | 1999-02-09 | - |
| Passive ownership stake (update) | SC 13G/A | 1999-01-28 | - |
| Passive ownership stake (update) | SC 13G/A | 1999-01-27 | - |
| Passive ownership stake (update) | SC 13G/A | 1999-01-11 | - |
| Quarterly report | 10-Q | 1998-12-09 | 1998-10-31 |
| Quarterly report | 10-Q | 1998-09-14 | 1998-08-01 |
| Employee plan annual report | 11-K | 1998-07-30 | 1998-01-31 |
| Passive ownership stake (update) | SC 13G/A | 1998-07-10 | - |
| Quarterly report | 10-Q | 1998-06-09 | 1998-05-02 |
| Proxy statement | DEF 14A | 1998-04-23 | 1998-05-27 |
| 10-K405 | - | 1998-04-23 | 1998-01-31 |
| Passive ownership stake (update) | SC 13G/A | 1998-02-17 | - |
| Passive ownership stake (update) | SC 13G/A | 1998-02-12 | - |
| Passive ownership stake (update) | SC 13G/A | 1998-02-12 | - |
| Passive ownership stake (update) | SC 13G/A | 1998-02-10 | - |
| Passive ownership stake | SC 13G | 1998-01-21 | - |
| Passive ownership stake (update) | SC 13G/A | 1998-01-05 | - |
| Quarterly report | 10-Q | 1997-12-15 | 1997-11-01 |
| Passive ownership stake | SC 13G | 1997-09-18 | - |
| Quarterly report | 10-Q | 1997-09-15 | 1997-08-02 |
| POS AM | - | 1997-09-05 | - |
| 424B4 | - | 1997-08-15 | - |
| S-3MEF | - | 1997-08-15 | - |
| S-3/A | - | 1997-08-08 | - |
| Securities registration | S-3 | 1997-08-05 | - |
| Employee plan annual report | 11-K | 1997-07-30 | 1997-02-01 |
| Quarterly report | 10-Q | 1997-06-16 | 1997-05-03 |
| Employee stock plan | S-8 | 1997-05-02 | - |
| Proxy statement | DEF 14A | 1997-04-29 | 1997-05-28 |
| 10-K405 | - | 1997-04-29 | 1997-02-01 |
| Passive ownership stake | SC 13G | 1997-02-14 | - |
| Passive ownership stake (update) | SC 13G/A | 1997-02-05 | - |
| Passive ownership stake (update) | SC 13G/A | 1997-02-04 | - |
| Passive ownership stake (update) | SC 13G/A | 1997-02-03 | - |
| Quarterly report | 10-Q | 1996-12-16 | 1996-11-02 |
| 424B4 | - | 1996-10-10 | - |
| Prospectus supplement | 424B5 | 1996-10-07 | - |
| Quarterly report | 10-Q | 1996-09-16 | 1996-08-03 |
| Employee plan annual report | 11-K | 1996-07-29 | 1996-02-03 |
| Quarterly report | 10-Q | 1996-06-18 | 1996-05-04 |
| Passive ownership stake (update) | SC 13G/A | 1996-02-12 | - |
| Passive ownership stake (update) | SC 13G/A | 1995-04-04 | - |
