[Trevor]

On 11/01/2020 4:00 am, Don Pearce wrote:

I've just been listening to More or Less, a BBC programme about
numbers, statistics and general misconception. They had an article
about exactly this question. They had a statement from The Royal
Observatory in Greenwich, the official home of time on Earth. The
message stated unequivocally that millennia, centuries and decades
start on the year ending in a one.

End of discussion.

There is no such thing as end of discussion when people are all talking
about different concepts, and that's before you even start arguing
linguistic definitions which is the cause of more internet arguments
that anything as far as I have seen.