Define a period

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How many working days in year 1968?

Here is the detail of the calculation:

Because 1968 is a leap year, it has 366 days.

Let's remove 52 saturdays and 52 sundays. It remains 262 days.

Now, let's remove 12 public holidays that do not fall during a weekend and we obtain 250 working days in 1968.

Here is the list of these 12 public holidays:

1. New Year's Day : Monday, 1 January, 1968
2. Seollal / Korean New Year Holiday : Monday, 29 January, 1968
3. Seollal / Korean New Year Holiday : Tuesday, 30 January, 1968
4. Seollal / Korean New Year Holiday : Wednesday, 31 January, 1968
5. Independence Movement Day : Friday, 1 March, 1968
6. Children's Day : Monday, 6 May, 1968
7. Memorial Day : Thursday, 6 June, 1968
8. Liberation Day : Thursday, 15 August, 1968
9. National Foundation Day : Thursday, 3 October, 1968
10. Chuseok / Midautumn Festival : Monday, 7 October, 1968
11. Hangeul Day : Wednesday, 9 October, 1968
12. Christmas Day : Wednesday, 25 December, 1968

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

1. Buddha's Birthday : Saturday, 4 May, 1968
2. Children's Day : Sunday, 5 May, 1968
3. Chuseok / Midautumn Festival : Saturday, 5 October, 1968
4. Chuseok / Midautumn Festival : Sunday, 6 October, 1968