The Transportation sector (IYT) has climbed 0.5% so far today and here are its biggest movers:

Company | Market Cap | Percentage Change |

Guangshen Railway Co. Ltd (NYSE:GSH) | $2.07 billion | -2.8% |

Atlas Air Worldwide Holdings (Nasdaq:AAWW) | $1.44 billion | +2.5% |

United Continental Holdings (NYSE:UAL) | $6.55 billion | +2.4% |

Hornbeck Offshore Services (NYSE:HOS) | $1.41 billion | -2.4% |

Grupo Aeroportuario del Pacifico (NYSE:PAC) | $2.33 billion | -2.1% |

Golar LNG (Nasdaq:GMLP) | $708.4 million | +1.7% |

Grupo Aeroportuario del Centro (Nasdaq:OMAB) | $849.8 million | -1.6% |

**Broker Summary: Charles Schwab Online Brokerage**

**Guangshen Railway Co. Ltd**(NYSE:GSH) has fallen 2.8% and is currently trading at $14.77 per share. So far today, the company's volume is 19,302 shares, 0.4 times the average daily volume. When a stock price moves up or down, watching the volume is a good way of identifying how significant that shift is. Investment valuation ratios provide investors with an estimation, albeit a simplistic one, of the value of a stock. The dividend yield is measured by taking the annual dividends per share and dividing that number by the stock price. GSH's dividend yield is 4.6%. It is important to remember that dividends are only one component of a stock's return and capital appreciation (or decline) must also be considered when evaluating a security. SEE: Dividend Yield For The Downturn

**Atlas Air Worldwide Holdings**(Nasdaq:AAWW) has moved up 2.5% and is currently trading at $55.90 per share. So far today, the company's volume is 95,033 shares. Price change alone is not enough to know how a stock is doing. Volume is an important secondary indicator used to confirm trends suggested by price movement. In making a decision about a potential or existing investment, valuation ratios are useful as a basis for seeing whether the stock price is too high, reasonable, or a bargain. The price/earnings to growth (PEG) ratio can reveal value what price/earnings (P/E) ratios alone may not so that if a company has a high P/E ratio (an indication that its stock is overpriced) but its earnings are growing very quickly, the PEG ratio may reveal that the company is actually fairly valued, or perhaps even a bargain. AAWW's PEG ratio of 0.86 is in line with the industry average. Because of the adjustment for earnings growth rate, the PEG ratio is somewhat more useful than many formulas for comparing companies in different industries.

**United Continental Holdings**(NYSE:UAL) has increased to a share price of $20.18, a 2.4% rise. So far today, the company's volume is two million shares, in keeping with its current three-month average. A stock's volume conveys how excited investors are about it. Valuation ratios like the price to earnings (P/E) ratio, the price to earnings growth (PEG) ratio, the price to sales (P/S) ratio, the price to book (P/B) ratio, and the dividend yield are useful in determining how attractive a potential or existing investment is. The price/book value ratio is calculated by dividing the current stock price by the company's book value per share. UAL has a P/B ratio of 4.1 which shows that its share price is higher than its book value. This high share price relative to asset value is likely to indicate that the company has been earning a very high return on its assets. One problem with the P/B value ratio is that it can be difficult to calculate the true book value of a company, so investors should be aware that many measures of book value may provide only a rough estimate, and should be taken with a grain of salt. SEE: How Buybacks Warps The Price-To-Book Ratio

**Hornbeck Offshore Services**(NYSE:HOS) is trading at $38.94 per share, down 2.4%. So far today, the company's volume is 182,888 shares. This is about the same trading activity as there was yesterday. Volume is an important indicator because it indicates how significant a price shift is. When estimating the value of a particular investment, valuation ratios provide a good basis for assessing the value of an individual stock. Perhaps one of the most widely-used stock analysis tools is the price-to-earnings ratio, or P/E. HOS' P/E ratio of 39.1 is above the industry average of 13.24. This could mean that the market is expecting big things over the next few months or years. To determine the P/E ratio, an investor divides the market price of the stock by the earnings-per-share (EPS) of the stock. SEE: Understanding The P/E Ratio

**Grupo Aeroportuario del Pacifico**(NYSE:PAC) is down 2.1% to reach $40.65 per share. At 21,377 shares, the company's volume so far today is 0.7 times its current daily average. If a stock price makes a big move up or down, volume lets us know the significance of that move. While investment valuation ratios are useful tools in estimating the attractiveness of an investment, remember that it is important to look at a company's historical performance and compare the company ratios with its competitors and industry overall. In a nutshell, the price/sales ratio shows how much Wall Street values every dollar of the company's sales. The P/S ratio for PAC is a high 5.35. This could be a good sign if the share price increases. It is important to compare P/S ratios for companies in the same industry, as ratios can vary quite widely for companies in different industries.

**Golar LNG**(Nasdaq:GMLP) is currently trading at $31.15 per share, a 1.7% increase. So far today, 28,894 shares have changed hands. If a stock price moves on high volume, this means that the change is a significant one. Looking at a company's valuation ratios is a good way of getting a basic idea as to its value as an investment. The easy-to-calculate debt ratio is helpful to investors looking for a quick take on the leverage for a company. GMLP has a high debt ratio of 97%. This means that most of the company's assets are financed through debt. As with all financial ratios, a company's debt ratio should be compared with the industry average or similar companies.

After a decline of 1.6%,

**Grupo Aeroportuario del Centro**(Nasdaq:OMAB) has hit a share price of $16.77. At 1,400 shares, the company's volume so far today is 0.6 times its average over the past three months. When a stock price moves up or down, watching the volume is a good way of identifying how significant that shift is. Investment valuation ratios can be very useful in determining the value of a stock, but it is very important to keep in mind that while some financial ratios have general rules (or a broad application), in most instances it is a prudent practice to look at a company's historical performance and use peer company/industry comparisons to put any given company's ratio in perspective. The debt-equity (D/E) ratio is a leverage ratio. OMAB has a low debt-equity ratio of 26%. This shows that the company's assets are financed primarily through equity. This easy-to-calculate ratio provides a general indication of a company's equity-liability relationship and is helpful to investors looking for a quick take on a company's leverage.

**The Bottom Line**On any given day, a particular stock may see positive or negative change in its share price. Paying close attention to the previous ratios will help you identify key times to adjust your strategy. Keep in mind that all these ratios should be compared against historical numbers and industry information in order to get a more complete picture.