According to health experts, childhood asthma rates have decreased by a third over the past decade.
There a likely to be number of reasons for the drop, such as it being diagnosed more selectively nowadays, as well as changes to diet and air quality.
But experts were also surprised to find levels of hay fever and eczema have remained fairly consistent over the last 10 years.
Asthma is typically thought of as being an allergic condition, and allergy also causes hay fever and eczema.
They said that if asthma rates are dropping and hay fever and eczema are not, it suggests that allergy may not be that important to asthma after all.