The Frontier series is the seventh series of banknotes of the Canadian dollar released by the Bank of Canada, first circulated in 2011. The polymer banknotes were designed for increased durability and to incorporate more security features over the preceding 2001 Canadian Journey series. The notes feature images that focus on historic Canadian achievements and innovation. Printed on polymer, the 2011 Frontier series was the first series issued by the Bank of Canada printed on a material other than paper. The 2011 Frontier series was followed by the 2018 series. The banknotes were designed by the Canadian Bank Note Company, which also prints the banknotes. They were revealed in June 2011. To familiarize Canadians with the new banknotes, each banknote was introduced through national and regional unveiling events and advertising campaigns before being put into circulation. The $100 banknote was released into circulation on 14 November 2011, the $50 banknote on 26 March 2012, and the $20 banknote on 7 November 2012. The $5 banknote was unveiled by Chris Hadfield from the International Space Station during Expedition 35 and first circulated on 7 November 2013. The $10 banknote was first circulated the same day after a ceremony at Pacific Central Station in Vancouver. Canada is the largest of over 30 nations, and the first G8 country, to use polymer thin films for printing currency. Background The primary impetus for the new banknotes was "the need to stay ahead of counterfeiters". By 2002, 10% of retailers in some parts of Canada refused to accept the $100 banknotes of the 1986 Birds of Canada series in financial transactions, and by 2004, the counterfeit ratio for Canadian currency had risen to 470 parts per million (ppm). As of 2011, over half of all retail transactions in Canada were made using cash. Between 1995 and 1998, the Bank of Canada tested a substrate trademarked as "Luminus" consisting of a polymer core sheet layered between two paper sheets for use in printing banknotes. It printed 100,000 experimental $5 Birds of Canada banknotes. In June 1998, the Bank of Canada prepared to use Luminus as the substrate for the 2001 Canadian Journey series, but in December 1999, the manufacturer withdrew its supply bid because it could not produce the substrate at the scale required by the Bank of Canada for printing banknotes. The bank printed the 2001 Canadian Journey series on a cotton fibre substrate with