In the current session, the stock is trading at $359.96, after a 0.40% spike. Over the past month, Penumbra Inc. (NYSE:PEN) stock increased by 13.56%, and in the past year, by 31.99%. With performance like this, long-term shareholders are optimistic but others are more likely to look into the price-to-earnings ratio to see if the stock might be overvalued.Comparing Penumbra P/E Against Its PeersThe P/E ratio is used by long-term shareholders to assess the company's market performance against aggregate marke ...