Define a period

...

How many working days in year 2054?

Here is the detail of the calculation:

Because 2054 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 2054.

Here is the list of these 10 public holidays:

1. 신정 : Thursday, 1 January, 2054
2. Seollal / Korean New Year Holiday : Monday, 9 February, 2054
3. 삼일절 : Monday, 2 March, 2054
4. 어린이날 : Tuesday, 5 May, 2054
5. 석가탄신일 : Friday, 15 May, 2054
6. 추석 : Tuesday, 15 September, 2054
7. 추석 : Wednesday, 16 September, 2054
8. 추석 : Thursday, 17 September, 2054
9. 한글날 : Friday, 9 October, 2054
10. 성탄절 : Friday, 25 December, 2054

And here are the 6 public holidays falling on a weekend:

1. Seollal / Korean New Year Holiday : Saturday, 7 February, 2054
2. Seollal / Korean New Year Holiday : Sunday, 8 February, 2054
3. 삼일절 : Sunday, 1 March, 2054
4. 현충일 : Saturday, 6 June, 2054
5. 광복절 : Saturday, 15 August, 2054
6. 개천절 : Saturday, 3 October, 2054