Ed Del Grande, a plumber, has an advice column in The Seattle Times. He responded to one query about home toilets by describing how the color of a toilet may indicate its vintage:

1920s: Rich pastels like autumn brown reflected fashion trends, and the surplus of beige left over from World War I found its way into our homes.

1930s: As the home became the focus of more activities, cozy neutrals like peach blow gave way to rich colors like dark green and maroon.

1940s: During the war years, the fashion and plumbing industries restricted the number of new colors. Some soil-hiding colors like olive green did appear.

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