I was taking a money management quiz from the MoneySmart government website. This was one of the questions: Question 4. If Laura deposited $20 a week in a high interest savings account with an interest rate of 6% for her newborn son, how much money would he have when he turns 21? I did a calculation on Excel assuming no tax and it gave the correct answer (about $43,000). However, in reality, wouldn't regular taxes severely reduce the final amount to well below $43,000?