Define a period

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How many working days in year 1960?

Here is the detail of the calculation:

Because 1960 is a leap year, it has 366 days.

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

Now, let's remove 9 public holidays that do not fall during a weekend and we obtain 252 working days in 1960.

Here is the list of these 9 public holidays:

1. New Year's Day : Friday, 1 January, 1960
2. Preseren's Day : Monday, 8 February, 1960
3. Easter Monday : Monday, 18 April, 1960
4. Resistance Day : Wednesday, 27 April, 1960
5. May Day Holiday : Monday, 2 May, 1960
6. Assumption Day : Monday, 15 August, 1960
7. Reformation Day : Monday, 31 October, 1960
8. All Saints' Day : Tuesday, 1 November, 1960
9. Independence and Unity Day : Monday, 26 December, 1960

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

1. New Year Holiday : Saturday, 2 January, 1960
2. Easter : Sunday, 17 April, 1960
3. May Day : Sunday, 1 May, 1960
4. Whitsunday : Sunday, 5 June, 1960
5. Statehood Day : Saturday, 25 June, 1960
6. Christmas Day : Sunday, 25 December, 1960