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LONG-TERM INCENTIVE PLANS - Stock option activity (Details) - Stock options | 12 Months Ended
--- | ---
Dec. 31, 2019 Options R$ / shares | Dec. 31, 2018 Options R$ / shares
Number of shares |  |
Balance, beginning of year | Options | 15,480 | 292,391
Options Exercised | Options |  | (33,499)
Options Forfeited | Options | (15,480) | (243,412)
Balance, end of year | Options |  | 15,480
Average exercise price in the year |  |
Beginning of year | R$ / shares | R$ 16.72 | R$ 17.91
Options Exercised | R$ / shares |  | 14.86
Options Forfeited | R$ / shares | 16.72 | 18.62
End of year | R$ / shares |  | R$ 16.72

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