 This represents a population growth rate of 1.1%.The age distribution, , in Therwil is; 592 children or 6.2% of the population are between 0 and 6 years old and 1,441 teenagers or 15.0% are between 7 and 19.Of the adult population, 945 people or 9.9% of the population are between 20 and 29 years old.