#### Eternal calendar to determine the day of the week by the new style #### How to use the eternal calendar

If we want to determine which day of the week is, for example, 21 March 1953, we do the following:
1. In the column “The first two numbers of the year” we find the row showing the first two numbers of the year (in this case 19). In the table “The second two numbers of the year” we find the column containing the second two numbers of the year (in this case 53). In the table of capital letters (middle section) we find the letter corresponding to the intersection of the respective row and column (in this case C).
2. In the column “Months” we find the row containing the number of the sought month (in this case III), and on the same row in the table of capital letters we find the column of the letter we have already found (in this case C).
3. In the bottom right-hand section of the table “Days of the month” we find the row containing the day we want (in this case 21). The intersection of this row with the column obtained in 2. above gives us in the column “Days of the week” the sought day of the week (in this case Sat - Saturday).
4. Leap years are marked in bold in the column of the second two numbers of the year. In the column of months we must differentiate between January and February in leap years, which are marked in bold. While in the old style all years ending in “00” are leap years, in the new style only the years whose first two numbers divide by 4 without residual are leap years. In Bulgaria the last day of the old style calendar is 31 March 1916. Instead of 1 April 916 we must calculate 14 April 1916 by the new style of the Gregorian calendar.