定义一个时期

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How many working days in year 2021?

Here is the detail of the calculation:

Because 2021 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 4 public holidays that do not fall during a weekend and we obtain 257 working days in 2021.

Here is the list of these 4 public holidays:

1. Jour de l'An : 星期五, 2021, 01, 1
2. Indépendance : 星期一, 2021, 03, 1
3. Vendredi Saint : 星期五, 2021, 04, 2
4. Jeudi de l'Ascension : 星期四, 2021, 05, 13

And here are the 3 public holidays falling on a weekend:

1. Fête du Travail : 星期六, 2021, 05, 1
2. Fête Nationale suisse : 星期日, 2021, 08, 1
3. Noël : 星期六, 2021, 12, 25