In the CCC it say:
2042: The second precept ("You shall confess your sins at least once a year.") ensures preparation for the Eucharist by the reception of the sacrament of reconciliation, which continues Baptism's work of conversion and forgiveness.83
In the CIC it says:
Kathy grew up with the first version and therefore thought the obligation was absolute. But the CIC says only grave sins must be confessed once a year, which is the way I learned it and have always taught it. I think the CCC should match the CIC on this. Interestingly, the footnote in the CCC cites the CIC canon 989!
Can. 989 All the faithful who have reached the age of discretion are bound faithfully to confess their grave sins at least once a year.