Educational background (spouse)
- Category of junior high school (spouse)
- High school (spouse)
- Vocational school (spouse)
- Junior college or College of technology (spouse)
- College or University (spouse)
- Graduate school (spouse)
- Year of graduation from the last school attended (spouse) [1st wave - 6th wave]
- Year of graduation from the last school attended (spouse) [7th wave - ]
- Preparatory school