Category 1 Category 2 Category 3 Category 4 Title 180TB/Year 159-216MB/s 1 million hours 3 years   Category 1 Category 2 Category 3 Category 4 Title 300TB/Year 216-230MB/s 1.2 million hours 5 years   Category 1 Category 2 Category 3 Category 4 Title 550TB/Year Up to 237MB/s 2 million hours 5 years