=SUM(表2:表3!A1)/(COUNTIF(表2!A1,"<>0")+COUNTIF(表3!A1,"<>0"))
可以写成：=IF(OR(表2!A1,表3!A1),SUM(表2:表3!A1),AVERAGEA(表2:表3!A1))
=if(or(表2!A1=0,表3!A1=0),MAX(表2！，A1,表3!A1),AVERAGE(表2:表3!A1) )
=SUM(表2:表3!A1)/COUNT(表2:表3!A1)
