Define a period

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How many working days in year 1979?

Here is the detail of the calculation:

Because 1979 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 9 public holidays that do not fall during a weekend and we obtain 252 working days in 1979.

Here is the list of these 9 public holidays:

1. Нова Година : Monday, 1 January, 1979
2. Празник после Нове Године : Tuesday, 2 January, 1979
3. Божићни празник : Monday, 8 January, 1979
4. Дан државности Србије : Thursday, 15 February, 1979
5. Дан после Дана државности Србије : Friday, 16 February, 1979
6. Велики петак : Friday, 20 April, 1979
7. Васкршњи понедељак : Monday, 23 April, 1979
8. Празник рада : Tuesday, 1 May, 1979
9. Празник после Празника рада : Wednesday, 2 May, 1979

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

1. Божић : Sunday, 7 January, 1979
2. Васкршња субота : Saturday, 21 April, 1979
3. Васкрс : Sunday, 22 April, 1979
4. Дан примирја : Sunday, 11 November, 1979