| Loss per common share |
| | | | | | | | | | | | | | | | | | | Three Month Period Ended September 30, 2018 | | | Three Month Period Ended September 30, 2017 | | | Nine Month Period Ended September 30, 2018 | | | Nine Month Period Ended September 30, 2017 | | Numerator: | | | | | | | | | | | | | | | | | Net loss attributable to Navios Holdings common stockholders | | $ | (1,816 | ) | | $ | (28,332 | ) | | $ | (67,965 | ) | | $ | (114,309 | ) | Less: | | | | | | | | | | | | | | | | | Declared and undeclared dividend on preferred stock and on unvested restricted shares | | | (2,566 | ) | | | (2,555 | ) | | | (7,679 | ) | | | (7,859 | ) | Plus: | | | | | | | | | | | | | | | | | Tender Offer – Redemption of preferred stock Series G and Series H including $702 and $972 of undeclared preferred dividend cancelled for the three and nine months of 2017, respectively | | | — | | | | 615 | | | | — | | | | 1,119 | | | | | | | | | | | | | | | | | | | Loss attributable to Navios Holdings common stockholders, basic and diluted | | $ | (4,382 | ) | | $ | (30,272 | ) | | $ | (75,644 | ) | | $ | (121,049 | ) | | | | | | | | | | | | | | | | | | Denominator: | | | | | | | | | | | | | | | | | Denominator for basic and diluted net loss per share attributable to Navios Holdings common stockholders — weighted average shares | | | 119,423,135 | | | | 117,535,234 | | | | 119,423,025 | | | | 116,260,640 | | | | | | | | | | | | | | | | | | | Basic and diluted net losses per share attributable to Navios Holdings common stockholders | | $ | (0.04 | ) | | $ | (0.26 | ) | | $ | (0.63 | ) | | $ | (1.04 | ) | | | | | | | | | | | | | | | | | |
|
| | | | | | | | | | | | | | Year ended December 31, 2017 | | | Year ended December 31, 2016 | | | Year ended December 31, 2015 | Numerator: | | | | | | | | | | | | Net loss attributable to Navios Holdings common stockholders | | $ | (165,910) | | | $ | (303,823) | | | $ | (134,112) | Declared and undeclared dividend on preferred stock and on unvested restricted shares | | | (10,421) | | | | (15,909) | | | | (16,202) | Tender Offer – Redemption of preferred stock Series G and H including $972 and $5,063 of undeclared preferred dividend cancelled for the year ended December 31, 2017 and December 31, 2016, respectively | | | 1,033 | | | | 46,627 | | | | — | Loss available to Navios Holdings common stockholders, basic and diluted | | $ | (175,298) | | | $ | (273,105) | | | $ | (150,314) | | | | | | | Denominator: | | | | | | | | | | | | Denominator for basic and diluted net loss per share attributable to Navios Holdings stockholders — adjusted weighted shares | | | 116,673,459 | | | | 107,366,783 | | | | 105,896,235 | | | | | | | | | | | | | Basic and diluted net loss per share attributable to Navios Holdings stockholders | | $ | (1.50) | | | $ | (2.54) | | | $ | (1.42) | | | | | | | | | | | | |
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