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v3.19.1

EARNINGS (LOSS) PER SHARE (EPS) - Diluted (Details) - BRL (R$) R$ / shares in Units, R$ in Thousands | 12 Months Ended
--- | ---
Dec. 31, 2018 | Dec. 31, 2017 | Dec. 31, 2016
Allocated net income available to Common and Preferred shareholders |  |  |
Net income (loss) available to owners of parent | R$ 2,303,868 | R$ (359,360) | R$ (2,890,811)
Weighted - average number of shares outstanding |  |  |
Earnings per share - Diluted (Common and Preferred Shares) | R$ 1.34 | R$ (0.21) | R$ (1.70)
Common shares |  |  |
Allocated net income available to Common and Preferred shareholders |  |  |
Net income (loss) available to owners of parent | R$ 774,279 | R$ (120,267) | R$ (969,954)
Adjustment to net income in respect to the potential increase in number of shares outstanding, as a result of options granted to acquire stock of Gerdau | (6,515) |  |
Net income (loss) available to owners of parent including effects of dilutive shares | R$ 767,764 |  |
Weighted - average number of shares outstanding |  |  |
Weighted-average number of shares outstanding | 571,929,945 |  |
Preferred shares |  |  |
Allocated net income available to Common and Preferred shareholders |  |  |
Net income (loss) available to owners of parent | R$ 1,529,589 | R$ (239,093) | R$ (1,920,857)
Adjustment to net income in respect to the potential increase in number of shares outstanding, as a result of options granted to acquire stock of Gerdau | 6,515 |  |
Net income (loss) available to owners of parent including effects of dilutive shares | R$ 1,536,104 |  |
Weighted - average number of shares outstanding |  |  |
Weighted-average number of shares outstanding | 1,129,851,598 |  |
Potential increase in number of preferred shares outstanding in respect of stock option plan | 14,440,860 |  |
Total | 1,144,292,458 |  |

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