Roman numerals:
M = 1000
MM = 2000
X = 10
I = 1
MMXI = 2000 + 10 + 1 = 2011
New Year's Eve is not a holiday, but a lot of people leave work at noon.
Some people go to parties and count down the New Year at midnight.
This blog is mainly to explain a different English language expression every day. Sometimes I post other stuff. I also have a YouTube channel which is mostly about computer software: https://www.youtube.com/englishspacedog