Supplementary is a subtheme of Duplo that consists of 6 sets that ran from 1982 to 1994. Most sets were released in 1987 which accounted for 2 sets. As of today, the average annual growth of all the sets in Duplo Supplementary is around 3.1% per year. The current value of all sets in new/factory sealed condtion is $241.35.
The LEGO DUPLO theme is designed for children ages 1 to 5. It features DUPLO figures which are much larger than minifigures and DUPLO blocks which are about twice the length, width, and height of a standard System brick.