Zheng Liu and Mark Spiegel at the San Francisco Fed wrote a really nice letter on demographics and asset rates, summarizing a lot of great academic perform on the question. For example, a rise in energy charges can lead to decrease sales, reduce earnings and lower stock prices. Stock rates, nonetheless, are determined by expectations of the future, which must, by definition, be unknown. I can not advise buying any stock since I am not a licensed economic advisor. I laid out the case why I believe Apple is nonetheless undervalued at its current cost.