general_fact: 156 is the number of years that Hong Kong was under British colony rule.
math_fact: 156 is a repdigit in base 5 (1111).
trivia: 156 is the width in miles of a crater formed by an asteroid that may have hit Earth 1.8 billion years ago, according to researchers from the University of Toronto and Geological Survey of Canada.
historical_date: June 4th is the day in 1970 that Tonga gains independence from the United Kingdom.