Reverse DCF in years of advantage

Use the competitive-advantage-period model of M06 Solution 6.6 with the BEL inputs of 15.7.4: $\text{NOPAT}_0 = \text{₹}5{,}831$ cr, $g = 15\%$, $R = 35\%$, $W = 12.53\%$, net cash ₹9,143.9 cr, 730.98 crore shares, price ₹407.20.

(a) Compute the no-growth value per share, $(N_1/W + \text{net cash})/\text{shares}$ with $N_1 = \text{NOPAT}_0(1+g)$. (b) Compute the value per share for $T = 10$ and $T = 20$. (c) Solve for the advantage period $T^*$ implied by the market price (treat $T$ as continuous). (d) Holding $T = 10$, solve for the implied growth $g^*$. (e) Repeat (b) for $T = 10$ and (c) with $W = 10.53\%$. Explain why lowering $W$ by two points shortens $T^*$ by more than eleven years, and what that says about which input to argue about.