10% is the figure we quit on — we don’t want to buy equities when the real return we expect is less than 10%, whether interest rates are 6% or 1%. It’s arbitrary. 10% is not that great after tax.
Mugner: We’re guessing at our future opportunity cost. Warren is guessing that he’ll have the opportunity to put capital out at high rates of return, so he’s not willing to put it out at less than 10% now. But if we knew interest rates would stay at 1%, we’d change. Our hurdles reflect our estimate of future opportunity costs.
We could take the $16 billion we have in cash earning 1.5% and invest it in 20-year bonds earning 5% and increase our current earnings a lot, but we’re betting that we can find a good place to invest this cash and don’t want to take the risk of principal loss of long-term bonds [if interest rates rise, the value of 20-year bonds will decline].
Source: Berkshire Hathaway Annual Meeting