The given function is:
[tex]y=(1.68)^{\frac{t}{3}}[/tex]Hence at t=1 and t=2 the values are:
[tex]\begin{gathered} y_1=(1.68)^{\frac{1}{3}}=1.8878 \\ y_2=(1.68)^{\frac{2}{3}}=1.4132 \end{gathered}[/tex]Hence the percentage change is given by:
[tex]\Delta y=\frac{y_2-y_1}{y_1}\times100=\frac{1.4132-1.8878}{1.8878}\times100=-25.1404[/tex]Hence y reduces by 25.14% from year 1 to year 2.
