The discontinuation of red, plus the general changes in society due to the United States' participation in World War II, caused a slump in sales of the larger serving pieces from the early 1940s. Prior to this reduction in the number of shapes offered, only one or two very specialized shapes had been discontinued and those by 1938. These early discontinued items, such as covered onion soup bowls in turquoise glaze and mixing bowl covers in any color, are today quite rare.