You are approximately 30 now, which means 20 more years, to make
money, if the employers still want to employ you after 40 y.o.
Think it's quite hard to get job after 50 y.o. (not trying to be
pessimistic, but have to face reality, it is harder to get job at
50).
If retire at 60 (don't take into account you working in Macs for 10
years), then maybe live another 20 years. Say you managed to save
another $250,000 for CPF, monthly expenses for you and wife after
retirement $1,500 p.m. ($18,000 p.a.). Interest rates of 3%
(meaning you earn 3% when you leave your money in bank or
cpf)
$250,000 = ($18,000 / 0.03) - ($18,000 / (0.03)(1 + 0.03)^n)
LN (18,000 / 10,500) = n LN (1.03)
0.538996501 = n 0.029558802
n = 18.23 years
Provided you don't have any medical contingencies, your CPF will be
just enough to cover you and your wife's basic necessities.
Good luck.
