Define a period

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How many working days in year 1963?

Here is the detail of the calculation:

Because 1963 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 14 public holidays that do not fall during a weekend and we obtain 247 working days in 1963.

Here is the list of these 14 public holidays:

1. New Year's Day : Tuesday, 1 January, 1963
2. Seollal / Korean New Year Holiday : Thursday, 24 January, 1963
3. Seollal / Korean New Year Holiday : Friday, 25 January, 1963
4. Independence Movement Day : Friday, 1 March, 1963
5. Buddha's Birthday : Wednesday, 1 May, 1963
6. Children's Day : Monday, 6 May, 1963
7. Buddha's Birthday : Thursday, 30 May, 1963
8. Memorial Day : Thursday, 6 June, 1963
9. Liberation Day : Thursday, 15 August, 1963
10. Chuseok / Midautumn Festival : Tuesday, 1 October, 1963
11. Chuseok / Midautumn Festival : Wednesday, 2 October, 1963
12. Chuseok / Midautumn Festival : Thursday, 3 October, 1963
13. Hangeul Day : Wednesday, 9 October, 1963
14. Christmas Day : Wednesday, 25 December, 1963

And here are the 2 public holidays falling on a weekend:

1. Seollal / Korean New Year Holiday : Saturday, 26 January, 1963
2. Children's Day : Sunday, 5 May, 1963