More than one-third of high-net worth investors in the United States are active buyers of art, according Art Basel and UBS Global Art Market Report published on Wednesday.

The total value of art sales grew by 12% in 2017 to an estimated US$63.7 billion, the report says, reversing the market’s decline in the past couple of years.

The U.S. remains the world’s leading market, accounting for 42% of sales, followed by China at 21%, and the United Kingdom at 20%, the report says.

“Despite some remaining political volatility, robust growth in high-end global wealth, accelerating financial market returns, stronger consumer confidence and increased supply led to a much more favorable environment for sales,” says Clare McAndrew, founder of research and consulting firm, Arts Economics, in a statement. However, the increase in sales was largely driven by the top end of the market, McAndrew says.

“Away from this premium segment, performance was not all positive, with many businesses coming under pressure,” she says. “This divergence in performance is a continuing concern, particularly as the majority of employment and ancillary spending comes from the very many other businesses in the art trade below the top tier. To maximize its economic impact, the market needs to be functioning well at all levels.”

According to the report, a survey of U.S.-based high-net worth individuals (HNWIs) found that 35% report being active in the art and collectibles markets. Most HNWI collectors (73%) surveyed said that the passion for collecting art is an expression of their personality, while 63% said they are motivated by a desire to support arts and culture.

“Only 32% of collectors felt that the expected financial return on their investment was important, although this was higher (at 47%) for those with wealth over $5 million,” the report says. “The majority of the collectors surveyed (86%) reported that they had never sold a work from their collection.”

Of these active buyers, only 1% reported buying at prices over US$1 million. In fact, the most common price range was under US$5,000 (79% of respondents reported buying in this range). Additionally, 11% of respondents said that they have borrowed to purchase works of art or objects in their collections.