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20. SHAREHOLDERS' EQUITY (Details 1) - R$ / shares | 12 Months Ended |
--- | --- | ---
Dec. 31, 2018 | Dec. 31, 2017
Average buyback price | R$ 7.86 |
Number bought back | 7,409,500 |
Balance in treasury | 1,387,524,047 | 1,387,524,047
Buyback program 1 |  |
Board's Authorization | 3/13/2014 |
Authorized quantity | 70,205,661 |
Program Period | From 3/14/2014 to 4/14/2014 |
Average buyback price | R$ 9.34 |
Minimum and maximum buyback price | R$ 9,22 and R$ 9,45 |
Number bought back | 2,350,000 |
Balance in treasury | 2,350,000 |
Buyback program 2 |  |
Board's Authorization | 4/15/2014 |
Authorized quantity | 67,855,661 |
Program Period | From 4/16/2014 to 5/23/2014 |
Average buyback price | R$ 8.97 |
Minimum and maximum buyback price | R$ 8,70 and R$ 9,48 |
Number bought back | 9,529,500 |
Balance in treasury | 11,879,500 |
Buyback program 3 |  |
Board's Authorization | 5/23/2014 |
Authorized quantity | 58,326,161 |
Program Period | From 5/26/2014 to 6/25/2014 |
Average buyback price | R$ 9.21 |
Minimum and maximum buyback price | R$ 8,61 and R$ 9,72 |
Number bought back | 31,544,500 |
Balance in treasury | 43,424,000 |
Buyback program 4 |  |
Board's Authorization | 6/26/2014 |
Authorized quantity | 26,781,661 |
Program Period | From 6/26/2014 to 7/17/2014 |
Average buyback price | R$ 10.42 |
Minimum and maximum buyback price | R$ 9,33 and R$ 11,54 |
Number bought back | 26,781,661 |
Balance in treasury | 70,205,661 |
Buyback program 4 (2) |  |
Board's Authorization | 7/18/2014 |
Average buyback price |  |
Minimum and maximum buyback price | Not applicable |
Share cancelation | 60,000,000 |
Balance in treasury | 10,205,661 |
Buyback program 5 |  |
Board's Authorization | 7/18/2014 |
Authorized quantity | 64,205,661 |
Program Period | From 7/18/2014 to 8/18/2014 |
Average buyback price | R$ 11.40 |
Minimum and maximum buyback price | R$ 11.40 |
Number bought back | 240,400 |
Balance in treasury | 10,446,061 |
Buyback program 5 (2) |  |
Board's Authorization | 8/18/2014 |
Average buyback price |  |
Minimum and maximum buyback price | Not applicable |
Share cancelation | 10,446,061 |
Buyback program 6 |  |
Board's Authorization | 8/18/2014 |
Authorized quantity | 63,161,055 |
Program Period | From 8/19/2014 to 9/25/2014 |
Average buyback price | R$ 9.82 |
Minimum and maximum buyback price | R$ 9,47 and R$ 10,07 |
Number bought back | 6,791,300 |
Balance in treasury | 6,791,300 |
Buyback program 7 |  |
Board's Authorization | 9/29/2014 |
Authorized quantity | 56,369,755 |
Program Period | From 9/29/2014 to 2/29/2014 |
Average buyback price | R$ 7.49 |
Minimum and maximum buyback price | R$ 4,48 and R$ 9,16 |
Number bought back | 21,758,600 |
Balance in treasury | 28,549,900 |
Buyback program 8 |  |
Board's Authorization | 12/30/2014 |
Authorized quantity | 34,611,155 |
Program Period | From 12/31/2014 to 3/31/2015 |
Average buyback price | R$ 5.10 |
Minimum and maximum buyback price | R$ 4,90 and R$ 5,39 |
Number bought back | 1,841,100 |
Balance in treasury | 30,391,000 |
Buyback program 9 |  |
Board's Authorization | 03/31/2015 |
Authorized quantity | 32,770,055 |
Program Period | From 4/01/2015 to 6/30/2015 |
Balance in treasury | 30,391,000 |
Buyback program 9 (2) |  |
Board's Authorization | 04/20/2018 |
Authorized quantity | 30,391,000 |
Program Period | From 4/20/2018 to 4/30/2018 |
Average buyback price |  |
Minimum and maximum buyback price | Não aplicável |
Number bought back | 0.00 |
Share cancelation | 0.00 |
Disposal of shares | 22,981,500 |
Balance in treasury | 7,409,500 |

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