In 2015, [duty free] sales in the beauty category, which includes scent, makeup and skin care products, totaled $19.8 billion, with fragrance accounting for 43.6 percent, according to Generation Research, a travel analytics company.

But in 2014, the overall sales were $19.3 billion, with fragrance accounting for 48.7 percent and, in 2013, $17.5 billion and fragrance, 50.8 percent.

The decline in the percentage of fragrance sales, which can be attributed to factors including a decrease in disposable income in some countries, has been a wake-up call to businesses.

— Duty free fragrance spending is down. Read more at Following the Scent of More Perfume Sales at The New York Times.