On December 18, 2009, Cesar Cielo Filho of Brazil set a world record by swimming 50 m on a long course (50-m pool) in 20.91 sec. This record is 0.61 sec longer than the record on the 50-m short course (25-m pool), which was set by Roland Schoeman of South Africa on August 8, 2009. By what percent is the record for a short course faster than the record for a long course