Valuation experts have recommended using the finance formula equating real growth in net cash flows (g) to the plowback rate (k) times the real return on investment (r) as a more reasonable basis for estimating plowback in the steady-state perpetuity period of the standard value-driver DCF formula. Unfortunately, practitioners make two errors when estimating implied plowback as k = g ÷ r. The first error is to use the incorrect nominal formula k = G ÷ R that is still found in finance and valuation textbooks. The second error arises because there are two ways to define plowback in the value-driver DCF model. The problematic traditional definition measures plowback ratio as a function of accounting NOPAT (before it has been transformed into cash NOPAT by deducting incremental working capital), thereby including in the numerator not only net new investment, but also changes in incremental working capital. The authors call this accounting plowback, and show why it is generally inappropriate to estimate implied accounting plowback using the formula k = g ÷ r. The authors explain in detail why the cash plowback presented in Bradley Jarrell (2008) is generally appropriate for estimating implied plowback and why accounting plowback is more problematic in this application.

中文翻译：

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恒定增长 DCF 模型中的后推

估值专家建议使用财务公式，将净现金流量 (g) 的实际增长等同于折返率 (k) 乘以实际投资回报率 (r)，作为估算永续稳定期折返的更合理基础标准的价值驱动 DCF 公式。不幸的是，从业者在将隐含的反推力估计为 k = g ÷ r 时会犯两个错误。第一个错误是使用了错误的名义公式 k = G ÷ R，这在金融和估值教科书中仍然可以找到。第二个错误的出现是因为在价值驱动 DCF 模型中有两种定义后退的方法。有问题的传统定义将回馈率衡量为会计 NOPAT 的函数（在通过扣除增量营运资金转化为现金 NOPAT 之前），因此，分子中不仅包括净新投资，还包括增量营运资本的变化。作者将此称为会计倒退，并说明为什么使用公式 k = g ÷ r 估计隐含的会计倒退通常是不合适的。作者详细解释了为什么 Bradley Jarrell (2008) 中提出的现金回馈通常适用于估计隐含回馈，以及为什么会计回馈在此应用中更成问题。