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How many working days in year 1990?

Here is the detail of the calculation:

Because 1990 is not a leap year, it has 365 days.

Let's remove 52 saturdays and 52 sundays. It remains 261 days.

Now, let's remove 10 public holidays that do not fall during a weekend and we obtain 251 working days in 1990.

Here is the list of these 10 public holidays:

1. Neujahrstag : понедельник, 1 январь, 1990
2. Karfreitag : пятница, 13 апрель, 1990
3. Ostermontag : понедельник, 16 апрель, 1990
4. Tag der Arbeit : вторник, 1 май, 1990
5. Christi Himmelfahrt : четверг, 24 май, 1990
6. Pfingstmontag : понедельник, 4 июнь, 1990
7. Tag der Deutschen Einheit : среда, 3 октябрь, 1990
8. Reformationstag : среда, 31 октябрь, 1990
9. Weihnachtstag : вторник, 25 декабрь, 1990
10. Zweiter Weihnachtsfeiertag : среда, 26 декабрь, 1990

And here is the public holiday falling on a weekend:

1. Heilige Drei Könige : суббота, 6 январь, 1990