NEW YORK ( TheStreet) -- Shares of Fonar Corporation (Nasdaq: FONR) have taken a tremendous swing upward. The stock is trading at $5.17 as of 2:20 p.m. ET, 21.1% above Tuesday's closing price of $4.27. Volume is at 672,362, 1.5 times the daily average of 444,600. Fonar has a market cap of $25.6 million and is part of the health care sector and health services industry. Shares are up 150.6% year to date as of the close of trading on Tuesday. FONAR Corporation engages in the research, development, production, marketing, and service of magnetic resonance imaging (MRI) scanners for the detection and diagnosis of human diseases. The company has a P/E ratio of six, equal to the average health services industry P/E ratio and below the S&P 500 P/E ratio of 17.7. TheStreet Ratings rates Fonar as a hold. The company's strengths can be seen in multiple areas, such as its notable return on equity, revenue growth and increase in net income. However, as a counter to these strengths, we find that the company has not been very careful in the management of its balance sheet. You can view the full Fonar Ratings Report. See our top % gaining stocks list for other stocks that are soaring today, or get investment ideas from our investment research center.