Custom Masking Timestamp

[#1]

Hello, Im trying to mask a timestamp so that we can only see the year but not the dates or time. is it possible?

I fouind this solution in the forums but it doesnt work. 

cast(mask(cast(to_date({col}) as date), 'x', 'x', 'x', -1, '1', 1, 0, -1) as timestamp)