[tex]Rate of change =\frac{Increase in acres}{Number of years}[/tex]
[tex]Rate of change =\frac{810,000-550,000}{2012-2003}[/tex]
[tex]Rate of change =\frac{260,000}{9}[/tex]
Rate of change = 28,888.88
Hence, the average rate of change in the number of acres is 28,889 per year approximately.