为什么本金也要收税？

问题如下：

Johnson is a tax adviser who provides tax awareness advice to private clients. One of Johnson’s clients is Lily. who currently has $10 million invested in a tax-deferred account earning 8% per year. Lily will sell the investment at the end of the five years, withdraw the proceeds from the sale in a lump sum (withdrawn are taxed at a 20% rate.), and use the proceeds to purchase the villa.

Lily asked Johnson to calculate the available after-tax wealth after five years.

The after-tax wealth in Lily’s tax-deferred account at the end of the five years will be closest to:

选项：

A.

$13,636,664

B.

$11,754,624

C.

$14,693,280

解释：

The value of a tax-deferred account compounds using the pre tax returns and pays tax only when assets are withdrawn from the account. Lily withdraws the proceeds at the end of her five-year holding period. The value of the assets withdrawn from the tax-deferred account is calculated as follows:

FV = PV × (1 + R)ⁿ × (1 − t),

where R is the portfolio pretax return.

FV = $10,000,000 × (1 + 0.08)⁵ × (1 − 0.20).

FV = $11,754,624.61.