! 2.15b.f90
!
! $Id: 2.15b.f90 1.2 2016/11/03 12:05:10 s Exp $
!
! bc, Before-tax cash flow  : �ňø‚«‘OƒLƒƒƒbƒVƒ…�Eƒtƒ��[
! nbc, nominal before-tax cash flow : –¼–Ú�ňø‚«‘OƒLƒƒƒbƒVƒ…�Eƒtƒ��[
! da,  Depletion            : Œ¸‰¿�ž‹p 
! ti,  Taxable income       : ‰Û�Å‘Î�ÛŽû‰v
! tax                       : �Å‹à
! ac, After-tax cash flow   : �ňø‚«ŒãƒLƒƒƒbƒVƒ…�Eƒtƒ��[
! tr, tax rate              : �Å—¦
! ir, infration rate        : ƒCƒ“ƒtƒŒ—¦
! ic, initial capital expenditure : �‰ŠúŽ‘–{”ï—p
! r,  discount rate         : ‹à—˜
! df, discount factor       : Š„ˆøŒW�”(2011-10-29‰ü)
! ny                        : ”N�”
! pv, present value of ac   : �ňø‚«ŒãƒLƒƒƒbƒVƒ…�Eƒtƒ��[‚ÌŒ»�݉¿’l

program ex2_15b

implicit none
character(80) :: fmt1, fmt2, fmt3
integer :: k, nk, ny
integer, dimension(0:10) :: i
double precision :: ic, ir, r, sumpv, tr
double precision, dimension(0:10) :: ac, bc, da, df, nbc
double precision, dimension(0:10) :: pv, tax, ti

! input
tr = 0.34d0
ir = 0.04d0
r  = 0.12d0
ic = 10.0d6
ny = 5
i(0:ny)  = (/(k, k = 0, ny)/)
bc(0:ny) = (/-ic, 2990.0d3, 2990.0d3, 2990.0d3, 2990.0d3, 2990.0d3/)
da(0:ny) = (/0.0d0, ic / ny, ic / ny, ic / ny, ic / ny, ic / ny/)
nk = 104

! calculate
nbc(0:ny) = bc(0:ny) * (1.0d0 + ir) ** i(0:ny)
do k = 0, ny
  if(nbc(k) -da(k) > 0) then
    ti(k) = nbc(k) - da(k)
  else
    ti(k) = 0.0d0
  end if
end do
tax(0:ny) = ti(0:ny) * tr
ac(0:ny)  = nbc(0:ny) - tax(0:ny)
df(0:ny)  = 1.0d0 / (1.0d0 + r) ** i(0:ny)
pv(0:ny)  = ac(0:ny) * df(0:ny)
sumpv = sum(pv(0:ny))

! output
fmt1 = '(1x,a3,a10,a13,a13,a9,a13,a7,a10,a9,a17)'
fmt2 = '(1x,i3,i10,f13.2,i13,i9,i13,i7,i10,f9.2,i17)'
fmt3 = '(a88, i17)'
print *, '2.15b.f90'
print fmt1, '”N','�ňø‘OCF','ƒCƒ“ƒtƒŒ”{—¦','–¼–Ú�ňø‘OCF','Œ¸‰¿�ž‹p', &
              '‰Û�Å‘Î�ÛŽû‰v','�Å‹à', '�ňøŒãCF','Š„ˆøŒW�”','�ňøŒãCFŒ»�݉¿’l'
print *, ('-', k = 1, nk)
do k = 0, ny
  print fmt2, k, nint(bc(k)), (1+ir)**k, nint(nbc(k)), nint(da(k)), &
              nint(ti(k)), nint(tax(k)), nint(ac(k)), df(k), nint(pv(k))
end do
print *, ('-', k = 1, nk)
print fmt3, 'Œ»�݉¿’l=', nint(sumpv)

stop
end program ex2_15b