Justine's rich uncle wants to give her $5,000 toward the purchase of a car. But since Justine doesn't plan to buy the car for at least another year, her uncle told her that she can have the money now, or he can wait and give her the money when she actually buys the car. Justine chooses to take the money now and deposit it in her savings account. After all, her deposit will yield 6% interest compounded annually. A year from now, her $5,000 will be worth $5,300. What financial concept does this scenario illustrate?