Answer: 8,647.28 Million

From the regression equation, $\hat{\beta}_0 = 5.105$ and $\hat{\beta}_1 = 0.044$. Under log-linear trend models, the predicted trend value is given by: $$ \ln Y_t = \hat{\beta}_0 + \hat{\beta}_1 t $$ $$ \Rightarrow Y_t = e^{\hat{\beta}_0 + \hat{\beta}_1 t} $$ Therefore: $$ Y_{90} = e^{5.105 + 0.044 \times 90} = e^{5.105 + 3.96} = e^{9.065} = 8,647.28 \text{ Million} $$ The calculation shows that the trend value estimate for the 90th week is 8,647.28 million.

Author: Nikitesh Somanthe