How many years are in a century, a millennium, and a decade?
By the convention of the Gregorian calendar, often known as the Gregorian Calendar, dates are expressed in terms of years:
| 1000 years | 1 century | 1 decade |
|---|---|---|
| 10 centuries | 10 decades | 10 years |
| 1 millennium | 100 years | 3652 days |
There are three distinct methods for calculating the millennium.
Method 1: 1 millennium is estimated from the years x001 to y002, or from 1 to 1010 for millennium I and 1002 to 2002 for millennium II.
Method 2: 1 the century is determined from the years x000 to x999, which translates to 1000 to 1999 being the millennium and 2000 to 2999 being the millennium 2000.
Method 3: 1 millennium is counted from the years x001 to y000, with the first millennium spanning the years 1 to 1000 AD, the second from 1001 to 2000, and the third from 2001 to 3000.
This computation places 2020 in the third millennium or the 2000 millennium.