# 3.3.jl
# 2024-09-05
# $Id: 3.3.jl 1.1 2024/10/29 11:45:44 s Exp $

# a,  age
# df, discount factor
# p , probability of becoming dead
# pv, present value of x
# r,  interest rate
# x,  cash flow

using Printf

# input
r = 0.08
istart =  90
iend   = 101
n = iend - istart
age=[90,   91,   92,   93,   94,   95,   96,   97,   98,   99,   100,  101 ]
x = [0,    10e3, 10e3, 10e3, 10e3, 10e3, 10e3, 10e3, 10e3, 10e3, 10e3, 10e3]
p = [0.07, 0.08, 0.09, 0.1,  0.1,  0.1,  0.1,  0.1,  0.1,  0.07, 0.05, 0.04]
pp= [1.0,  0.0,  0.0,  0.0,  0.0,  0.0,  0.0,  0.0,  0.0,  0.0,  0.0,  0.0 ]
j = [x for x=1:12]

# calculate
for i = 2:n+1
    pp[i] = pp[i - 1] - p[i - 1]
end
df = [1 / (1 + r) ^ (i-1) for i = 1:length(age)]
pv = [x1 * x2 * x3 for (x1, x2, x3) in zip(pp, x, df)]

# output
@printf("%s", "3.3.jl\n")
@printf("%8s%8s%8s%8s%8s%8s%8s\n", "i", "age", "p", "pp", "annuity", "df", "pv")
println(repeat("-", 56))
for i = 1:length(age)
  @printf("%8d%8d%8.2f%8.2f%8.0f%8.2f%8.0f\n", i-1, age[i], p[i], pp[i], x[i], df[i], pv[i])
end
println(repeat("-", 56))
@printf("%8s%16.2f%32d\n","sum",sum(p),sum(pv))
# end