 This represents a population growth rate of 0.1%.The age distribution, , in Birsfelden is; 570 children or 5.5% of the population are between 0 and 6 years old and 1,092 teenagers or 10.5% are between 7 and 19.Of the adult population, 1,278 people or 12.2% of the population are between 20 and 29 years old.