Вы можете использовать ADO в Excel.Запрос будет:
Select Code, WorkPackage, Max([date]), First([Name]), Sum([Hours])
From [Sheet1$]
Group By Code, WorkPackage
Ссылка: http://support.microsoft.com/kb/257819
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SELECT t.code, t.workPackage, Format([Date],"yyyy-ww") AS WeekNo,
Min(t.Date) AS MinOfDate, Max(t.Date) AS MaxOfDate,
Min(t.name) AS MinOfname, Sum(t.hours) AS SumOfhours
FROM [Sheet1$] t
GROUP BY t.code, t.workPackage, Format([Date],"yyyy-ww");