 One popular explanation is that the trend was started by junior high school girls, who would give handmade chocolate to boys to see if they returned their affections, and it later became commercialized in the mid-1950s, with the first Valentine's sale taking place in 1958 at Mary Chocolate.Harumichi Yamada from Tokyo Keizai University stated that the practice of giving chocolate occurred because women expressing their love to men was considered disgraceful, and confectioneries capitalized on chocolate as a way for them to profess their love; however, as the social status of women improved, Valentine's Day was later considered a day where women give chocolate to men, through which the custom emerged.Sachiko Horiguchi from Temple University, Japan Campus suggested that the custom first occurred in the 1980s where working women were obligated to give chocolate to their co-workers and bosses, as both of the Japanese corporate and gift-giving cultures made it appropriate for this exchange to take place.