Editing Implied volatility (section)

===Example===
A call option is trading at $1.50 with the [[underlying]] trading at $42.05. The implied volatility of the option is determined to be 18.0%. A short time later, the option is trading at $2.10 with the underlying at $43.34, yielding an implied volatility of 17.2%. Even though the option's price is higher at the second measurement, it is still considered cheaper based on volatility. 
The reason is that the underlying needed to hedge the call option can be sold for a higher price.