Today, we mostly refer to years in their full name: 2020 as "twenty twenty", or "two thousand twenty".
In the late 1900s, we were mostly using the short form: 1995 as "ninety five".
How did people refer to years a century ago? Did people say "twenty three" for 1923 (for example), or did they spell out the entire thing?
If yes, why aren't we doing the same now? What's different?
If no, when did the language shift occur?