Define a period

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How many working days in year 2087?

Here is the detail of the calculation:

Because 2087 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 13 public holidays that do not fall during a weekend and we obtain 248 working days in 2087.

Here is the list of these 13 public holidays:

1. 신정 : Wednesday, 1 January, 2087
2. Seollal / Korean New Year Holiday : Monday, 3 February, 2087
3. Seollal / Korean New Year Holiday : Tuesday, 4 February, 2087
4. 삼일절 : Monday, 3 March, 2087
5. 어린이날 : Monday, 5 May, 2087
6. 현충일 : Friday, 6 June, 2087
7. 광복절 : Friday, 15 August, 2087
8. 추석 : Wednesday, 10 September, 2087
9. 추석 : Thursday, 11 September, 2087
10. 추석 : Friday, 12 September, 2087
11. 개천절 : Friday, 3 October, 2087
12. 한글날 : Thursday, 9 October, 2087
13. 성탄절 : Thursday, 25 December, 2087

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

1. Seollal / Korean New Year Holiday : Sunday, 2 February, 2087
2. 삼일절 : Saturday, 1 March, 2087
3. 석가탄신일 : Saturday, 10 May, 2087