JP Morgan Funds Twitter account posted a nice graph on Twitter today showing that, even while the S&P is trading near an all time high, this rally could go a lot further. The S&P 500 is still trading below the average forward P/E of the last 30 years according to the graph. According to this chart the S&P 500 is fairly valued and we are not experiencing some kind of bubble. Of course earnings will need to keep growing in the future to keep justifying a higher price.