Definition: In this task, you're given passages that contain mentions of a time duration related quesry and we are supposed to write answer to a question that involves event “frequency", which refers to how often an event is likely to be repeated. For example, "taking showers" typically occurs ~5 times a week, "going to saturday market" usually happens every few weeks/months, etc. 
 Note that a lot of the questions could have more than one correct answers. We only need a single most-likely answer. Please try to keep your "answer" as simple as possible. Concise and simple "answer" is preferred over those complex and verbose ones.  
Input: Sentence: Chopin's music remains very popular and is regularly performed, recorded and broadcast worldwide. The world's oldest monographic music competition, the International Chopin Piano Competition, founded in 1927, is held every five years in Warsaw. The Fryderyk Chopin Institute of Poland lists on its website over eighty societies world-wide devoted to the composer and his music. The Institute site also lists nearly 1,500 performances of Chopin works on YouTube as of January 2014. 
Question: How often is the International Chopin Piano Competition held?
Output:
every five years