Number of warrants outstanding |
Weighted average exercise price |
|||||||
Outstanding, December 31, 2011 |
4,087 | 3.28 | ||||||
Granted |
(1,773 | ) | 1.86 | |||||
Expired |
(131 | ) | 46.25 | |||||
Outstanding, December 31, 2012 |
2,183 | 1.85 | ||||||
Exercised |
(1,571 | ) | 1.86 | |||||
Outstanding, December 31, 2013 |
612 | $ | 1.83 |