"I am not sure you can claim that the risk free rate was "the...

"I am not sure you can claim that the risk free rate was "the thing" that made the stock double over the past 6 months. If you look at the 10yr Australian government bond yield vs the stock price, you can see that the risk free rate is at the same level it was back in August last year, well before covid entered the equation."

Valuation is all about future expectations.

To the extent that Covid induced an expectation over the past 6 months that bond yields would remain depressed for a long time would have informed the market's valuation of ARB.

Conversely, to the extent that the prospect of a vaccine now changes that expectation of the level of bond yields, hence the discount rate, induces a change in the market's perception of the value of future cash flows.

Which goes to highlight, once again, the sheer futility of investing is on the basis of trying to predict macro-economic variables.

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