Sales of prestige beauty products -- that is, beauty products sold mostly in department stores -- grew across the board in the second quarter of this year, except in one area: nail products. While sales of prestige beauty products increased to $2.5 billion in the U.S., up 5 percent from the same period last year, sales of nail products, which have already been declining for several seasons, fell another 11 percent, according to a recently released study from NPD Group.

One might assume a declining interest in nail art might be responsible for sliding sales in department stores and in drugstores, but a Google Trends search for "nail art" shows that interest in creatively painted nails has remained steady over the past four years. So what is it? Are Americans not painting their nails at home as much anymore? Or, having stocked up on nail products in the early part of the decade, do they simply not need anymore? NPD doesn't say.

A few other highlights from the report:
  • Sales of makeup products increased 8 percent to $1.0 billion, the fastest-growing category. Sales of eye and lip makeup increased the most, making up nearly half of sales for the category.
  • Skincare sales were up 2 percent to $744 million.
  • Fragrance sales were up 5 percent to $632 million.
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