The rate of change can be defined as a change of anything we are measuring that happens over a specific time.
The formula for the rate of change in a period of time
[tex]m=\frac{\text{Junesales}-\text{Maysales}}{Maysales}\cdot100[/tex]Then,
[tex]\begin{gathered} m=\frac{131975-129800}{129800}\cdot100 \\ m=\frac{2175}{129800}\cdot100 \\ m=0.0168\cdot100 \\ m=1.68\text{\%} \end{gathered}[/tex]