An exponential decay function represents a quantity that has a decreasing halving time

Yes, the statement "An exponential decay function represents a quantity that has a decreasing halving time" is true. In addition, this process can be expressed by the following differential equation, where N is the quantity and λ (lambda) is a positive rate called the exponential decay constant: d N d t = − λ N . {\displaystyle {\frac {dN}{dt}}=-\lambda N.}