Task: Question Answering
Input (English): Passage: In 1989 Ricklefs was elected a Fellow of the Australian Academy of the Humanities. The Government of Australia awarded him in 2001 the Centenary Medal for service to Australian society and the humanities in the study of Indonesia. In 2010 he was elected as an erelid  of the Netherlands Koninklijk Instituut voor Taal-, Land- en Volkenkunde, one of only eight people currently recognised in this way. He was awarded the 2015 George McT. Kahin Prize of the Association for Asian Studies, ‘given biennially to an outstanding scholar of Southeast Asian studies from any discipline or country specialization to recognize distinguished scholarly work on Southeast Asia beyond the author's first book' for his work Islamisation and its opponents in Java: A political, social, cultural and religious history, c. 1930 to the present . In 2016 the Indonesian Ministry of Education and Culture presented Professor Ricklefs with its prestigious Cultural Award . In June 2017, Professor Ricklefs was made a member of the Order of Australia. 
Question: How many years after he was elected a fellow was the Centenary Medal for service to Australian given to him? 
Answer type: Number 
Output (English): 21.