问题如下：
An Australian investor currently holds a A$240 million equity portfolio. He is considering rebalancing the portfolio based on an assessment of the risk and return prospects facing the Australian economy. Information relating to the Australian investment markets and the economy has been collected in the following table:
Using the information in the table, calculate the expected annual equity return using the Grinold–Kroner model (assume no change in the number of shares outstanding).
选项：
A.6.25%
-3.45%
7.3%
解释：
A is correct.
The Grinold–Kroner model states that the expected return on equity is the sum of the expected income return (2.4%), the expected nominal earnings growth return (7.3% = 2.3% from inflation + 5.0% from real earnings growth) and the expected repricing return (–3.45%). The expected change in market valuation of –3.45% is calculated as the percentage change in the P/E level from the current 14.5× to the expected level of 14.0×: (14 – 14.5)/14.5 =–3.45%. Tus, the expected return is 2.4% + 7.3% – 3.45% = 6.25%.
解析：Grinold-Kroner model计算收益率时包含以下三个部分： the expected income return, the expected nominal earnings growth return 以及 the expected repricing return。那么我们就分别求解这三部分。
从表格中直接可得Expected annual income return= 2.4%
The expected nominal earnings growth return=Expected annual real earnings growth + Expected inflation rate=5%+2.3%=7.3%
对于The expected repricing return，我们可以通过预期P/E值与当前P/E值得变化率求出，即： (14−14.5)/14.5 =−3.45%.
所以最终的收益率为2.4% + 7.3%
– 3.45% = 6.25%.
为什么变化率是除以中间平均的P/Eb而不是比上beigining的那个呢。。？
