Please check the following, we think there might be a mistake.
The post-World War II period from 1945 until 1970 is recognized as one of the most creative artistic periods of the 20th century, spanning movements from Abstract Expressionism in New York in the 1940s to Pop Art that was popular mainly in England and the United States (from the late 1950s to early 1970s) . Works of artists who flourished in the late 1940s, 1950s and 1960s are typically featured in Christie's twice-yearly sales in London and New York.
Christie's is also the leading auction house for Contemporary Art sales, dedicated to art created after 1970. Focusing on the various artistic movements of this time, from Minimalism and Conceptualism to Graffiti Art, Brit Pop and the cutting-edge artistic expressions of the day, these sales break records and establish collecting trends.
Estimated sales: 7 per annum