! 5.12.f90
! 2024-10-09
! $Id: 5.12.f90 1.1 2024/11/02 12:08:38 s Exp $

! df : discount factor
! d : dividend
! r : interest rate
! g : growth rate
! v : value of the company

implicit none
integer  n, i(5),j
real(8)  d0, d1, d5, df(5), r, g1, g2, v0, v5, v6

! input
n  = 5
r  = 0.15
g1 = 0.10 ! for the next 5 years
g2 = 0.05 ! thereafter
d0 = 10000.0

! calculation
do j = 1, n
    i(j) = j
end do
d1 = d0 * (1.0 + g1)
df(1:n) = 1.0 / (1.0 + r) ** i(1:n)
v5 = sum(d1 * ((1.0 + g1) ** (i(1:n) - 1)) * df(1:n))
d5 = d1 * (1.0 + g1) ** (n - 1);
v6 = (1.0 + g2) * d5 / (r - g2) / (1.0 + r) ** n;
v0 = v5 + v6;

! output
print *,'5.12.f90'
print '(a5,f10.2)', "r ",  r
print '(a5,f10.2)', "g1", g1
print '(a5,f10.2)', "g2", g2
print '(a5,i10)',   "d0", int(d0)
print '(a5,i10)',   "d1", int(d1)
print '(a5,6f5.2)', "df", df
print '(a5,i10)',   "v5", int(v5)
print '(a5,i10)',   "d5", int(d5)
print '(a5,i10)',   "v6", int(v6)
print '(a5,i10)',   "v0", int(v0)
end