演出是可数，业绩是不可数名词

柯林斯英汉双解大辞典

performance /pəˈfɔːməns/ 

1.

可数名词 A performance involves entertaining an audience by doing something such as singing, dancing, or acting. 表演

例：

Inside the theatre, they were giving a performance of Bizet's Carmen.

他们正在剧院里演出比才的《卡门》。

例：

...her performance as the betrayed Medea.

…她出演被出卖的美狄亚。

2.

有变体名词 Someone's or something'sperformance is how successful they are or how well they do something. 业绩; 性能

例：

That study looked at the performance of 18 surgeons.

那项研究着眼于18位外科医生的业绩。

例：

The poor performance has been blamed on the recession and cheaper sports car imports.

业绩惨淡归咎于经济衰退和更便宜跑车的进口。