How much of the return on equities comes from income as opposed to capital? Given the trend towards buybacks, one might reasonably expect the income component to be lower for US than for UK and that is what I have found. While UK actuaries commonly used to assume it would be 50%, this was probably overstated (see here). Dependent upon the other assumptions made, the equity DVR is not that sensitive. Until the end of 2018, over periods of 15 years, the income component averaged 40.9% (UK) and a much lower 31.2% (US), making 40% growth reasonable for UK.
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