我如何只显示一次$ amount？

The project table

项目表

PID   ProjectName Phase PhaseName Price  
16-A  XYZ         1     Phase 1   0
16-A  XYZ         2     Phase 2   0
16-A  XYZ         3     Phase 3   0
17-A  ZYX         1     Phase 1   0
17-A  ZYX         2     Phase 2   0
PID   ProjectName Ph