July 24, 2007 Issuance | February 3, 2006 Issuance | December 15, 2005 Issuance | |||||||||
Warrants issued | 256,409 | 8,593 | 8,446,727 | ||||||||
Average strike price | $ | 20.00 | $ | 17.50 | $ | 17.50 | |||||
Volatility | 30.0 | % | 30.0 | % | 30.0 | % | |||||
Risk-free rate | 4.5 | % | 4.5 | % | 4.5 | % | |||||
Expected dividend yield | 0.0 | % | 0.0 | % | 0.0 | % | |||||
Expected term (years) | 8 | 10 | 10 | ||||||||
Calculated fair value per warrant | $ | 11.28 | $ | 8.89 | $ | 8.89 | |||||