Define a period

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How many working days in year 2040?

Here is the detail of the calculation:

Because 2040 is a leap year, it has 366 days.

Let's remove 52 saturdays and 53 sundays. It remains 261 days.

Now, let's remove 12 public holidays that do not fall during a weekend and we obtain 249 working days in 2040.

Here is the list of these 12 public holidays:

1. Seollal / Korean New Year Holiday : Monday, 13 February, 2040
2. 삼일절 : Thursday, 1 March, 2040
3. 어린이날 : Monday, 7 May, 2040
4. 석가탄신일 : Friday, 18 May, 2040
5. 현충일 : Wednesday, 6 June, 2040
6. 광복절 : Wednesday, 15 August, 2040
7. 추석 : Wednesday, 19 September, 2040
8. 추석 : Thursday, 20 September, 2040
9. 추석 : Friday, 21 September, 2040
10. 개천절 : Wednesday, 3 October, 2040
11. 한글날 : Tuesday, 9 October, 2040
12. 성탄절 : Tuesday, 25 December, 2040

And here are the 4 public holidays falling on a weekend:

1. 신정 : Sunday, 1 January, 2040
2. Seollal / Korean New Year Holiday : Saturday, 11 February, 2040
3. Seollal / Korean New Year Holiday : Sunday, 12 February, 2040
4. 어린이날 : Saturday, 5 May, 2040