18 December 1980
17 December19 December| w | MondayMonM | TuesdayTueT | WednesdayWedW | ThursdayThuT | FridayFriF | SaturdaySatS | SundaySunS |
|---|---|---|---|---|---|---|---|
| 6 Dec | Finlands nationaldag | |
| 7 Dec | Andra advent | |
| 10 Dec |  | Nobeldagen |
| 13 Dec | Luciadagen | |
| 14 Dec | Tredje advent | |
| 21 Dec | Fjärde advent | |
| 21 Dec | Vintersolståndet | |
| 23 Dec | | Drottningens födelsedag |
| 24 Dec | Julafton | |
| 25 Dec | | Juldagen |
| 26 Dec | Annandag jul | |
| 28 Dec | Värnlösa barns dag | |
| 31 Dec | Nyårsafton | |
| 7 Dec | New Moon |
| 15 Dec | Waning Crescent |
| 21 Dec | Full Moon |
| 29 Dec | Waxing Crescent |