If fragrance progression follows social norms (and many would say it does), then the increased popularity of eau de parfum in the 1980s might reflect the stereotypical wearer of that decade: bold, financially savvy and tending toward excess.
More concentrated than eau de cologne and eau de toilette, eau de parfum ranges from about 10 to 15 percent essential oils. The result is a fragrance that lasts a lot longer than cologne, up to five hours, so it requires less-frequent application (and women on the go rejoice). It's not so strong, however, that it needs to be applied as drops; eau de parfum is still light enough to be sold as a purse-worthy, high-volume spray (again, women on the go rejoice).
This type of fragrance puts the attention on the middle notes, which take over after the top notes fade. Middle notes, sometimes also known as "heart notes," are dominant from about 15 minutes to a couple of hours after application and are considered to be the core of the scent. Eau de parfum is more expensive than eau de cologne and eau de toilette, so it's a less popular variety. Since it lasts so much longer, though, and can be applied in smaller doses, many people find it to be an affordable formulation.
And then there's perfume, which few would ever call affordable. It's the original, the elite, the pure.