第一步的公式是什么意思

NO.PZ2020021204000034 问题如下 A bonthcliverein the cember 2018 ten-yeTreasury note futures contrais a bonwith maturity on April 15, 2026, thpays a coupon of 4% per annum.When the yielis 6% per annum(with semi-annucompounng) ， calculate the conversion factor for the bon The bons time to maturity on the first y of the livery months is seven years (cember 2018 to cember 2025) an4.5 months (January 2026 to miApril 2026).This is rounto seven years anthree months. The rty priof a seven yeanthree-month bonimmeately before the coupon payable in three months is ∑i=01421.03i+1001.0314=90.7039\sum_{i=0}^{14}\frac2{1.03^i}+\frac{100}{1.03^{14}}=90.7039∑i=014​1.03i2​+1.0314100​=90.7039when the yielis 6%. The rty priof the bonthree months earlier is90.70391.03=89.3732\frac{90.7039}{\sqrt{1.03}}=89.37321.03​90.7039​=89.3732Subtracting the accrueinterest of 1, we get a clepriof 88.3732 anthe conversion factor is 0.8837. 10年债券，到期日是2026年4月15，起始日是2016年4月25？每半年付息一次，那在livery te，也就是2018年12月的时候，上一次付息是在2018年10月15日？那应计利息应该是2018年10月15日到2018年12月？为什么答案说是18年12月到19年4月之间的利息？

NO.PZ2020021204000034 问题如下 A bonthcliverein the cember 2018 ten-yeTreasury note futures contrais a bonwith maturity on April 15, 2026, thpays a coupon of 4% per annum.When the yielis 6% per annum(with semi-annucompounng) ， calculate the conversion factor for the bon The bons time to maturity on the first y of the livery months is seven years (cember 2018 to cember 2025) an4.5 months (January 2026 to miApril 2026).This is rounto seven years anthree months. The rty priof a seven yeanthree-month bonimmeately before the coupon payable in three months is ∑i=01421.03i+1001.0314=90.7039\sum_{i=0}^{14}\frac2{1.03^i}+\frac{100}{1.03^{14}}=90.7039∑i=014​1.03i2​+1.0314100​=90.7039when the yielis 6%. The rty priof the bonthree months earlier is90.70391.03=89.3732\frac{90.7039}{\sqrt{1.03}}=89.37321.03​90.7039​=89.3732Subtracting the accrueinterest of 1, we get a clepriof 88.3732 anthe conversion factor is 0.8837. 没有精确的给4月x/10月x日付利息，导致算那个AI=1的时候比较抽象，想了半天，考试的时候是不是会给精确的能在计算器用日期公式算天数的呀

NO.PZ2020021204000034问题如下 A bonthcliverein the cember 2018 ten-yeTreasury note futures contrais a bonwith maturity on April 15, 2026, thpays a coupon of 4% per annum.When the yielis 6% per annum(with semi-annucompounng) ， calculate the conversion factor for the bon The bons time to maturity on the first y of the livery months is seven years (cember 2018 to cember 2025) an4.5 months (January 2026 to miApril 2026).This is rounto seven years anthree months. The rty priof a seven yeanthree-month bonimmeately before the coupon payable in three months is ∑i=01421.03i+1001.0314=90.7039\sum_{i=0}^{14}\frac2{1.03^i}+\frac{100}{1.03^{14}}=90.7039∑i=014​1.03i2​+1.0314100​=90.7039when the yielis 6%. The rty priof the bonthree months earlier is90.70391.03=89.3732\frac{90.7039}{\sqrt{1.03}}=89.37321.03​90.7039​=89.3732Subtracting the accrueinterest of 1, we get a clepriof 88.3732 anthe conversion factor is 0.8837.1、这里写的coupon是每年，但是和半年复利矛盾啊？看解题的答案也是半年一次coupon和复利频次一样，老师，coupon的现金流频次是要和复利频次一样的吧？2、题目哪里能看出是每年10月，4月支付coupon？3、应计利息是1，是怎么得出来的？

NO.PZ2020021204000034问题如下 A bonthcliverein the cember 2018 ten-yeTreasury note futures contrais a bonwith maturity on April 15, 2026, thpays a coupon of 4% per annum.When the yielis 6% per annum(with semi-annucompounng) ， calculate the conversion factor for the bon The bons time to maturity on the first y of the livery months is seven years (cember 2018 to cember 2025) an4.5 months (January 2026 to miApril 2026).This is rounto seven years anthree months. The rty priof a seven yeanthree-month bonimmeately before the coupon payable in three months is ∑i=01421.03i+1001.0314=90.7039\sum_{i=0}^{14}\frac2{1.03^i}+\frac{100}{1.03^{14}}=90.7039∑i=014​1.03i2​+1.0314100​=90.7039when the yielis 6%. The rty priof the bonthree months earlier is90.70391.03=89.3732\frac{90.7039}{\sqrt{1.03}}=89.37321.03​90.7039​=89.3732Subtracting the accrueinterest of 1, we get a clepriof 88.3732 anthe conversion factor is 0.8837.烦请具体写下该类题怎么解答，多谢。

NO.PZ2020021204000034问题如下 A bonthcliverein the cember 2018 ten-yeTreasury note futures contrais a bonwith maturity on April 15, 2026, thpays a coupon of 4% per annum.When the yielis 6% per annum(with semi-annucompounng) ， calculate the conversion factor for the bon The bons time to maturity on the first y of the livery months is seven years (cember 2018 to cember 2025) an4.5 months (January 2026 to miApril 2026).This is rounto seven years anthree months. The rty priof a seven yeanthree-month bonimmeately before the coupon payable in three months is ∑i=01421.03i+1001.0314=90.7039\sum_{i=0}^{14}\frac2{1.03^i}+\frac{100}{1.03^{14}}=90.7039∑i=014​1.03i2​+1.0314100​=90.7039when the yielis 6%. The rty priof the bonthree months earlier is90.70391.03=89.3732\frac{90.7039}{\sqrt{1.03}}=89.37321.03​90.7039​=89.3732Subtracting the accrueinterest of 1, we get a clepriof 88.3732 anthe conversion factor is 0.8837.为什么要折三个月，利息为什么是1