Kelly Crow provides a timeline of Richter’s rise in value in the Wall Street Journal. It begins with MoMA’s 1995 purchase of a suite of paintings and continues with the museum’s retrospective in 2001 (11 years later the Tate would play its own role):

Two years after that, a lawyer and collector based in Zurich named Joe Hage began gathering auction prices and exhibit details about the works in Mr. Richter’s oeuvre. He started a website, gerhard-richter.com, and began posting the results online.

For newer, Internet-savvy collectors, Mr. Hage’s site has proved popular because of all that its tallying has revealed. Mr. Richter has created 3,000 paintings—fewer than Warhol’s 8,000 silk-screens but considerably more than Salvador Dalí’s 1,200 works. He’s also heavily traded, with more than 200 of his works turning up at auction every year, which provides buyers with a regular stream of price points to analyze. Museums own roughly 38% of his works, though, including half of his most coveted works, those large squeegee abstracts.

By 2006, […] Sotheby’s began shipping its top Richters to Hong Kong so potential bidders there could see his works. In May 2006, a bidder at Berlin’s Villa Griesbach auction house paid $1 million for Mr. Richter’s 1971 portrait of “Mao.” The following summer, the same painting came up for bid at Christie’s in London and sold for $2.5 million.

Then came the snowball: In February 2008, the artist’s eldest daughter, Betty, sold her 1983 “Candle” for $15.8 million, triple the high estimate, at Sotheby’s. Three months later, Mr. Abramovich dropped $15.1 million for Mr. Richter’s green-gray “Abstract Painting” from 1990. It was only priced to sell for up to $7 million. With that, collectors recalibrated Mr. Richter’s high bar to $15 million or more.

During the recession that followed, potential sellers of Mr. Richter’s masterworks largely sat on the sidelines, but by late 2010, as the market perked up again, a fresh set of collectors began embellishing their collections with Richters. That November, Sotheby’s got $13.2 million for his 1966 “Sailors,” a work that spent years in the New Museum Weserburg in Bremen. The buyers were Houston hedge-fund manager John Arnold and his wife, Laura.

A pivotal sale four months ago sealed the deal. At Sotheby’s in New York, London collectors Marc and Victoria Sursock offered up eight Richter abstracts; all sold for well over their asking prices, including the abstract that went to Ms. Safra for $20.8 million. Last month in London, collectors came back for more: Christie’s got $15.5 million for a green Richter abstract, while Sotheby’s sold a creamy abstract to a former Zurich nightclub owner, Carl Hirschmann, for $4.8 million.

The Top Selling Living Artist (Wall Street Journal)