Msg 116, Level 16, State 1, Line 6 Only one expression can be specified in the select list when the subquery is not introduced with EXISTS.

Hello,

Can anyone help me?

select year(po.rdata) as 'Ano',  sum(etotal) as 'Valorp' , (select year(fo.data),Sum(etotal)  FROM fo (nolock)  where  not exists ( select 1 from pl (nolock) where pl.adoc = fo.adoc and pl.cm = fo.doccode )  group by year(fo.data))as 'Valorap'    from po  group by year(po.rdata) order by year(po.rdata)

Error 
Msg 116, Level 16, State 1, Line 6 Only one expression can be specified in the select list when the subquery is not introduced with EXISTS.
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