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INVESTMENTS (Details) - BRL (R$) R$ in Thousands | 12 Months Ended
--- | ---
Dec. 31, 2017 | Dec. 31, 2016 | Dec. 31, 2015
INVESTMENTS |  |  |
Balance at beginning of period | R$ 798,844 | R$ 1,392,882 | R$ 1,394,383
Equity in earnings | (34,597) | (12,771) | (24,502)
Cumulative translation adjustment | (16,745) | (251,195) | 417,961
Capital increase | 362,857 |  | 40,524
Joint venture creation | 145,084 |  |
Contingent price complement | 65,500 |  |
Impairment of assets |  |  | (361,786)
Control acquisition |  |  | (20,929)
Effect of selling of subsidiary |  | (205,577) |
Dividends/Interest on equity | (40,644) | (124,495) | (52,769)
Balance at end of period | 1,280,299 | 798,844 | 1,392,882
Dona Francisca Energtica S.A. |  |  |
INVESTMENTS |  |  |
Balance at beginning of period | 90,796 | 89,595 | 124,211
Equity in earnings | 19,971 | 17,780 | 11,725
Contingent price complement | 65,500 |  |
Dividends/Interest on equity | (26,594) | (16,579) | (46,341)
Balance at end of period | 149,673 | 90,796 | 89,595
Armacero Industrial y Comercial S.A. |  |  |
INVESTMENTS |  |  |
Balance at beginning of period |  |  | 20,251
Equity in earnings |  |  | (1,933)
Cumulative translation adjustment |  |  | 2,611
Control acquisition |  |  | (20,929)
Corsa Controladora, S.A. de C.V. and subsidiaries |  |  |
INVESTMENTS |  |  |
Balance at beginning of period | 266,303 | 359,568 | 298,409
Equity in earnings | (6,533) | 12,155 | (7,574)
Cumulative translation adjustment | 17,512 | (105,420) | 68,733
Balance at end of period | 277,282 | 266,303 | 359,568
Corporacin Centro Americana del Acero S.A. and subsidiaries |  |  |
INVESTMENTS |  |  |
Balance at beginning of period |  | 216,272 | 435,568
Equity in earnings |  | 23,705 | 9,053
Cumulative translation adjustment |  | (36,134) | 134,749
Impairment of assets |  |  | (361,786)
Effect of selling of subsidiary |  | (203,843) |
Dividends/Interest on equity |  |  | (1,312)
Balance at end of period |  |  | 216,272
Other Associate companies |  |  |
INVESTMENTS |  |  |
Balance at beginning of period |  | 2,084 | 1,581
Cumulative translation adjustment |  | (350) | 503
Effect of selling of subsidiary |  | (1,734) |
Balance at end of period |  |  | 2,084
Joint Ventures, North America |  |  |
INVESTMENTS |  |  |
Balance at beginning of period | 56,492 | 60,733 | 40,152
Equity in earnings | 5,725 | 13,533 | 14,432
Cumulative translation adjustment | 5,081 | (9,492) | 11,265
Dividends/Interest on equity | (14,050) | (8,282) | (5,116)
Balance at end of period | 53,248 | 56,492 | 60,733
Gerdau Corsa S.A.P.I de C.V. |  |  |
INVESTMENTS |  |  |
Balance at beginning of period | (19,269) | 88,785 | 109,930
Equity in earnings | (110,773) | (96,306) | (88,690)
Cumulative translation adjustment | (33,078) | (11,748) | 27,021
Capital increase | 178,670 |  | 40,524
Balance at end of period | 15,550 | (19,269) | 88,785
Gerdau Metaldom Corp. |  |  |
INVESTMENTS |  |  |
Balance at beginning of period | 404,522 | 575,845 | 364,281
Equity in earnings | 33,505 | 16,362 | 38,485
Cumulative translation adjustment | (7,606) | (88,051) | 173,079
Dividends/Interest on equity |  | (99,634) |
Balance at end of period | 430,421 | R$ 404,522 | R$ 575,845
Gerdau Summit Aos Fundidos e Forjados S.A. |  |  |
INVESTMENTS |  |  |
Equity in earnings | 15,460 |  |
Capital increase | 184,187 |  |
Balance at end of period | 199,647 |  |
Diaco S.A. |  |  |
INVESTMENTS |  |  |
Equity in earnings | 8,048 |  |
Cumulative translation adjustment | 1,346 |  |
Joint venture creation | 145,084 |  |
Balance at end of period | R$ 154,478 |  |

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