Technically, a leapling will have fewer "birthday anniversaries" than their age in years. This phenomenon is exploited when a person claims to be only a quarter of their actual age, by counting their leap-year birthday anniversaries only: for example, in Gilbert and Sullivan's 1879 comic opera "The Pirates of Penzance", Frederic the pirate apprentice discovers that he is bound to serve the pirates until his 21st "birthday" (that is, when he turns 88 years old, since 1900 was not a leap year) rather than until his 21st "year".