I want to retire in 20 years. I think that I need $500,000. I have $200,000 set aside right now. If I earn 5.25%, will I have enough? How much do I need to have today in order to achieve that?

To determine whether you will have enough to retire in 20 years with $500,000, we can use the concept of future value calculation.

Future value (FV) is the value of an investment at a specific point in the future, assuming a specified rate of return. In your case, you want to calculate how much you need to have today (present value, PV) in order to achieve a future value (FV) of $500,000 in 20 years, with an interest rate of 5.25%.

To calculate the present value (PV), we can use the formula:

PV = FV / (1 + r)^n

Where:
- PV is the present value (the amount you need to have today)
- FV is the future value you want to achieve ($500,000)
- r is the interest rate per period (5.25% or 0.0525)
- n is the number of periods (20 years)

Using this formula, let's calculate the present value (PV):

PV = $500,000 / (1 + 0.0525)^20

PV = $500,000 / (1.0525)^20

PV ≈ $217,383.56

So, approximately $217,383.56 is the amount you need to have today in order to achieve a future value of $500,000 in 20 years with an interest rate of 5.25%. Since you already have $200,000 set aside, you are currently short of approximately $17,383.56 to reach your target.