Define a period

...

How many working days in year 1907?

Here is the detail of the calculation:

Because 1907 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 12 public holidays that do not fall during a weekend and we obtain 249 working days in 1907.

Here is the list of these 12 public holidays:

1. New Year's Day : Tuesday, 1 January, 1907
2. Seollal / Korean New Year Holiday : Tuesday, 12 February, 1907
3. Seollal / Korean New Year Holiday : Wednesday, 13 February, 1907
4. Seollal / Korean New Year Holiday : Thursday, 14 February, 1907
5. Independence Movement Day : Friday, 1 March, 1907
6. Children's Day : Monday, 6 May, 1907
7. Memorial Day : Thursday, 6 June, 1907
8. Liberation Day : Thursday, 15 August, 1907
9. Chuseok / Midautumn Festival : Monday, 23 September, 1907
10. National Foundation Day : Thursday, 3 October, 1907
11. Hangeul Day : Wednesday, 9 October, 1907
12. Christmas Day : Wednesday, 25 December, 1907

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

1. Children's Day : Sunday, 5 May, 1907
2. Buddha's Birthday : Sunday, 19 May, 1907
3. Chuseok / Midautumn Festival : Saturday, 21 September, 1907
4. Chuseok / Midautumn Festival : Sunday, 22 September, 1907