Sotheby’s, the New York-based auctioneer of art and collectibles, reported a 13 percent decrease in second-quarter profit that fell below analyst expectations because of a change in the sales calendar and a loss on a painting sold during the period.

Net income was $67.6 million, or 96 cents a share, in the quarter ended June 30, compared with $77.6 million, or $1.11, in the same period last year, Sotheby’s said Friday. The company was expected to report earnings of $1.22 a share, according to the average of five analysts in a Bloomberg survey.