Amended description and geographic bounding limits for area 1293. Added areas 3176-78 and projCRSs 22521-22 and 22525. Deprecated areas 1621-22; changed area code for projCRS 22523 from 1621 to 3177; changed area code for projCRS 22524 from 1622 to 1818. Changed area code for tfm 1132 from 1053 to 1293. For datum 6225, changed datum origin coordinates to those given by IBGE; NIMA values and supersession info added as remarks. For CRSs 4225 and 22523-24, supersession info added as remarks.