NO.PZ2023052301000046
问题如下：
Consider a bond that has three years remaining to maturity, a coupon of 4% paid semiannually, and a yield-to-maturity of 4.60%. Assuming it is 12 days into the first coupon period and a 30/360 basis, the bond’s annualized Macaulay duration is closest to:
选项：
A.1.8764 years.
2.8386 years.
2.8553 years.
解释：
B is correct.
Assuming it is 12 days into the first coupon period 的意思是还有12天进入第一个付息日吗？
macaulay duration是站在什么时点去计算的，如果现在还有12天进入第一个付息日，那用于计算第一笔现金流权重的t应该是12/180，并且PV也是CF/(1+2.3%)^(12/180)，为什么答案是168/180？
请老师再帮忙解释下如何理解。谢谢。