The origin of the calendar currently imposed in a large part of the world. It is the Gregorian calendar, originated in Europe in the year 1528. This came as a substitute for the system that at that time reigned in society: the Julian calendar. Imposed by the great Julius Caesar in the year 46 a.C. After centuries of imposition, Pope Gregory XIII decided to transform this method. Promulgating a new style through a reform document known as Inter Gravissimas.
The new version consists of 365 solar days, with the exception of leap years. These already existed in the Julian calendar, between February 23 and 24. However, Gregory XIII placed this extra day at the end of the same month. The change was introduced to correct the gap between the duration of the tropical year and the traditional calendar year. Each time the last number of the year is a multiple of four (2004, 2008, 2012, 2016 …), we will be facing a leap year.
Pope Gregory XIII established the current calendar. To deduce the number of weeks that this specific time interval has, it is only necessary to perform a simple mathematical calculation.
The exact figure is obtained by dividing the number of days that the year has, by the number of days that make up the week. Resulting in a total of 52 weeks in 1 year, exactly 52,1429 in one year.
These will not always be complete. Many of them do not start on a Monday and end on a Sunday. Since it depends on the precise day on which the new year begins. If we only counted the intact, we would have 50 weeks with a few days difference.
In the case of the leap years, the calendar would also be composed of 52 weeks. However, on this occasion and due to the imbalance mentioned above, we should add two more days that remain outside the sum.
In a leap Year
A leap year has 52 weeks and 1 day.
In a normal Year
A normal year has 52 weeks and 2 days.
Not Including Weekends
If you don’t want to count weekends then the number of days is 261 so the number of week is exactly 37,28 weeks (261/7).