Lin is valuing a 1-year CDS contact  which will pay the buyer 75% of face value of bond issued by X company. Lin estimates that the risk netural default probability is 5% per year. Risk-free rate is 3%. Assuming defaults can only occur halfway through the year and accrued premium is paid after a default. what is the CDS spread?

这是2013 practice，答案里面说payoff现值=payment现值，这个思路我能理解。不过payment=

我不明白这里为什么乘以0.5，有哪个大牛可以解释一下吗？