When a date says X next to it

[UniqueShaker]

Hi

I am hoping someone can help. I study with the OU and i was looking at a date to put in my references and the date says 200X. What on earth does this mean? I've never seen an X in a date before

Thanks

200X is a placeholder meaning the exact year is uncertain, but that it falls somewhere in the 2000s. It is used either when a source was created sometime in that decade, but the specific year isn't known or varies between editions or sources. If you're referencing I would check for a more precise date or cite it as 200X.

Thank you so much. I had a feeling that might be the case but I wasn't sure whether 200X was acceptable to put on the referencing list. I'll do a bit more digging to see if I can find a specific year. Thanks so much.