Yann,
Because your date is in a string format, you would need to cast your object to be in a date format and then use Jeam's suggestion of _add_years function.
Example:
cast([YYYY].[XXXX].[DateCourte].[DateCourte], AS DATE) = _add_years ( current_date; -1)
Alternatively
TO_DATE([YYYY].[XXXX].[DateCourte].[DateCourte], 'YYYY-MM-DD') = _add_years ( current_date; -1)
Jeanie