In my database, the dates are retained as days elapsed since/before 01/01/1970, which I understand to be a Unix date format, eg. today is 23rd May 2018 and the value is 17674.

I'm trying to run a `select` statement against a column in a date table to show only the year. 


If I run this: 

    datepart(year, c.cko_date)

I get dates that are in the 1940s (they should be the last couple of years).

When I run 

    select datepart(year, getdate()) 

it correctly tells me the date is 2018.

Any suggestions about what I'm doing wrong?