Provide analysis and evidence of price performance of original vintage posters as an asset class and some price performance of individual posters over the last 15 years. Supply examples of poster price records by asset category (film, advertising, travel, ski, sport, propaganda and war) as well as poster designer (Cassandre, Mucha, Stenberg Brothers and others). Price performance should be based on auction sale results (Christies, Swann Galleries, Heritage and others). Benchmark price performance vs stock indices in the UK and USA. Provide some outlook for this asset class.