因为你的数据是扩展的,直接相减会出现笛卡尔积
可以参考这个,跨报表块与跨sheet原理一样
跨sheet过滤单元格-https://help.finereport.com/doc-view-2381.html
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REPLACE(GREPARRAY(report14~A4+report14~B4, LEFT(item,LEN(A4))=A4),A4,"")-REPLACE(GREPARRAY(report15~A4+report15~B4, LEFT(item,LEN(A4))=A4),A4,"")