Patterns have been sold under the brand name Simplicity since 1927. (They’re still active today.) This 1974 advertisement, aimed at the teenage market, plays up the value of separates: why, you could come up with nine different looks with but a single top!
Forty-odd years later, I wonder if anyone made all nine of those skirts. And I admit, 6789 (wrap skirt with patch pockets) reminds me of someone.