哪位excel高手解释下面公式的含义啊,有个图片供大家参考,急,

哪位excel高手解释下面公式的含义啊,有个图片供大家参考,急,
=SUM(OFFSET(OFFSET(INDIRECT(B$1&"月!$A$1"),MATCH("NB R&D allocation",INDIRECT(B$1&"月!A:A"),0)-1,1,1),2,2,MATCH("Total NB R&D expense",INDIRECT(B$1&"月!A:A"),0)-MATCH("NB R&D allocation",INDIRECT(B$1&"月!A:A"),0)-1,16)*IF(OFFSET(OFFSET(INDIRECT(B$1&"月!$A$1"),MATCH("NB R&D allocation",INDIRECT(B$1&"月!A:A"),0)-1,1,1),1,2,1,16)=$A2,1,0)*IF(OFFSET(OFFSET(INDIRECT(B$1&"月!$A$1"),MATCH("NB R&D allocation",INDIRECT(B$1&"月!A:A"),0),1,1),1,MATCH("Total NB R&D expense",INDIRECT(B$1&"月!A:A"),0)-MATCH("NB R&D allocation",INDIRECT(B$1&"月!A:A"),0)-1,1)=$A$1,1,0))