math_fact: 2017 is a value of n for which f(n) = f(n-1) + f(n-2).
trivia: 2017 is a number for which we're missing a fact (submit one to numbersapi at google mail!).
historical_date: July 9th is the day in 1995 that the Navaly church bombing is carried out by the Sri Lankan Air Force killing 125 Tamil civilian refugees.