How to make DataVoyager recognize a variable as temporal?

In David Anthoff’s “Intro to the Queryverse”, at 9:30 ( Intro to the Queryverse, a Julia data science stack | David Anthoff - YouTube ), he passes a dataset to voyager() (from DataVoyager.jl) and one of the variables is recognized as a measure of time. I wonder why, what about the data tells voyager() that this is indeed time?

I have a dataset with one column named “Year”, wherein the year is stored as an integer. This is not automatically recognized and I wonder what is the most sensible transformation of this that can get recognized as temporal by voyager().