Most people don't understand Roman numerals so movie makers use these numerals to disguise the fact when the movie was actually released.
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How do you "know" without asking them, that "most" people don't understand Roman numerals (they can always find out!), and why should film-makers want to disguise release dates? Roman numerals have always been common in publishing generally.
To disguise the fact the year that the film was actually released.
To disguise the fact when the film was actually released because most people don't understand Roman numerals and don't like watching repeats.
Back then all people knew where roman numerals. So they used it as numbers to date when the movie will come out, are for something else. Today we use 1 2 3 4 5 6 7 8 9 10,etc...........That's why it's impotant to know your roman numerals. I know all of mines.
It is Good Friday and today's date is April 22 2011 which in Roman numerals is IV-XXII-MMXI
The date 03.04.1989 is written in roman numerals as III.IV.MCMLXXXIX
The date 17-04-2009 in Roman Numerals would be XVII.IV.MMIX
The date 06.12.1983 in Roman numerals would be VI.XII.MCMLXXXIII
2017 is the equivalent of MMVII in Roman numerals
The date 15-04-1990 can be represented by the Roman numerals XV.IV.MCMXC
The date 25-03-2006 in Roman numerals would be XXV.III.MMVI
The date 01-06-1981 in Roman numerals is I.VI.MCMLXXXI
The date 19-02-1986 written in Roman numerals would be XIX.II.MCMLXXXVI