# weekyear - script and chart function

This function returns the year to which the week number belongs according to ISO 8601. The week number ranges between 1 and approximately 52.

Syntax:

weekyear(expression)

**Return data type:** integer

Examples and results:

Examples and results

| Example | Result |
| --- | --- |
| `weekyear( '1996-12-30' )` | returns 1997, because week 1 of 1997 starts on 1996-12-30 |
| `weekyear(<br>'1997-01-02' )` | returns 1997 |
| `weekyear(<br>'1997-12-28' )` | returns 1997 |
| `weekyear(<br>'1997-12-30' )` | returns 1998, because week 1 of 1998 starts on 1997-12-29 |
| `weekyear(<br>'1999-01-02' )` | returns<br>1998, because week 53 of 1998 ends on 1999-01-03 |

Limitations:

Some years, week #1 starts in December, e.g. December 1997. Other years start with week #53 of previous year, e.g. January 1999. For those few days when the week number belongs to another year, the functions year and weekyear will return different values.