Specifically for Norway, but I'm sure this applies to some other countries as well. We are only able to put in age ratings for the current rating system, however many (many) older movies before this rating system has different age ratings which we can't enter due to not being recognized as a rating. The current Norwegian system has the ages: A (everyone), 6, 9, 12, 15, 18; however many old movies were rated for example 7, 10, 11 etc. This means it is not possible to enter the correct rating for these releases. A few specific examples of movies this affects:

• The Princess Bride: The theatrical release was rated 10, unable to use the correct age. Blu-ray release was rated 7, also not compatible.
• The Amazing Spider-Man 1 and 2: both rated 11, unable to use correct rating

Several old movies have this issue. For context, according to wikipedia the age ratings 5 and 10 were retired in 1994, 7 and 11 were retired in 2015 and 16 was retired in 1988