The ancient Romans would have worked out the equivalent of 1999 on an abacus counting board as MDCCCCLXXXXVIIII and then abridged it to IMM (2000-1) in written format which answers your question.
However, the equivalent of todays 1999 inRoman numerals when expressed as M+CM+XC+IX then they too become abridged to IMM as follows:-
M+CM = CMM
CMM+XC = XMM
XMM+IX = IMM
QED by David Gambell
The number 1999 in Roman numerals is MCMXCIX
MCMXCIX
The Roman numerals for 07-01-1999 are VII-I-MCMXCIX.
15th November, 1999 is XV. XI. MCMXCIX in Roman numerals.
it would be november,MCMXCIX
The number 1999 in Roman numerals is MCMXCIX
MCMXCIX
The Roman numerals for 07-01-1999 are VII-I-MCMXCIX.
15th November, 1999 is XV. XI. MCMXCIX in Roman numerals.
it would be november,MCMXCIX
1999 = mcmxcix mcmxcix; m = 1000, cm = 900, xc = 90, ix = 9
MIM is an incorrect way of writing 1999 in roman numerals. 1999 should be written MCMXCIX.
XIX-V-MCMXCIX
III-V-MCMXCIX
November is 11 so XI-XX-MCMXCIX
MCMXCIX EDIT: A shorter way to write it is MIM
In today's notation of Roman numerals: XII-XXVIII-MCMXCIX But during Tthe Roman era the eqivalent of 1999 was probably written out simply as IMM (2000-1)