RM<=6.941: 19.9
RM>6.941
|    RM<=7.437
|    |    CRIM>7.393: 14.4
|    |    CRIM<=7.393
|    |    |    DIS<=1.886: 45.7
|    |    |    DIS>1.886: 32.7
|    RM>7.437
|    |    TAX<=534.500: 45.9
|    |    TAX>534.500: 21.9

