Thus the year number did not change until 25 March, so taking 1558 as an example, the dates ran as follows: So if you see a document dated any time between January and 24 March before 1752, be aware that in modern terms, you need to add a year.
Some documents will be dated not by the calendar year but by the regnal year - how long the ruling monarch had been on the throne.
Cases of backdating employee stock options have drawn public and media attention.
According to a study by Erik Lie, a finance professor at the University of Iowa, more than 2,000 companies used options backdating in some form to reward their senior executives between 19.
In 1582 Pope Gregory XIII had reformed the calendar, then in use, known as the Julian Calendar (named after Julius Caesar).
The Julian Calendar did not correspond exactly to the solar year.
The new Gregorian Calendar cut 10 days from the year in adjustment.