Thx Sergey, you nailed it again.
Do you think i can also retrieve in this same SELECT the percentage growth ( or reduction ) between CurRes and OldRes?


>Try

SELECT ;
>    Clients.ClientName, ;
>    Sum(IIF(BETWEEN(Reservations.date, ReportFrom, ReportTo), 1, 0) as CurRes,;
>    Sum(IIF(BETWEEN(Reservations.date, ReportFrom, ReportTo), Reservations.Amount, 0) as CurAmount, ;
>    Sum(IIF(BETWEEN(Reservations.date, OldFrom, OldTo), 1, 0) as OldRes,;
>    Sum(IIF(BETWEEN(Reservations.date, OldFrom, OldTo), Reservations.Amount, 0) as OldAmount, ;
>  FROM Reservations JOIN Clients ;
>        ON Reservations.ClientCode=Clients.Code  ;
>  WHERE between( Reservations.date, ReportFrom, ReportTo ) ;
>         OR between( Reservations.date, OldFrom, OldTo ) ;
>  GROUP BY Clients.Code ;
>INTO CURSOR crsResult	
>