Despite a relative slowdown in the global art market, the online art market grew by 15 percent, to $3.75 billion, last year, according to Robert Read, head of art and private clients for Hiscox. The online art market’s share of the total art market also grew last year, from 7.4 percent in 2015 to 8.4 percent. While that may seem small, it is roughly equivalent to e-commerce sales’ share of the total retail market, which reached 8.3 percent last year, according to the U.S. census.