How many working days in year 2149?
Here is the detail of the calculation:
Because 2149 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 2149.
 Here is the list of these 10 public holidays: 
 
 1. Jour de l'An : среда, 1 январь, 2149 
2. Lundi de Pâques : понедельник, 31 март, 2149 
3. Fête du Travail : четверг, 1 май, 2149 
4. Jeudi de l'Ascension : четверг, 8 май, 2149 
5. Lundi de la Pentecôte : понедельник, 19 май, 2149 
6. Fête de la Communauté flamande : пятница, 11 июль, 2149 
7. Fête Nationale : понедельник, 21 июль, 2149 
8. Assomption : пятница, 15 август, 2149 
9. Fête de l'Armistice : вторник, 11 ноябрь, 2149 
10. Noël : четверг, 25 декабрь, 2149 
And here is the public holiday falling on a weekend:
1. Toussaint : суббота, 1 ноябрь, 2149