The amount of air we take in one breath is called Tidal Volume (TV). For a new born infant it is approx. 50 ml and can be as low as 20 ml for a premature baby.

TV for an average adult is between 550 - 700 ml.
At rest adults have about 20 breaths per minute (BPM).
When people work, or exercise, or they are under stress, the rate goes up.

0.7 l TV x 20 BPM x 60 min x 24 hours = 20,160 l air enter into person's lungs.