SELECT Sum(arrivi),Sum(presenze),('ITA')As TipoMov,DATENAME(year,@DallaData1) As Anno,DATENAME(MONTH,data) As Mese
FROM Dbo.Tab_movimenti
WHERE
    Codcomune Between 1 and 91 AND
    Codcategoria IN(11,12) AND
    Codnazione IN(901,902) AND
    data BetWeen @DallaData1 AND @AllaData1
    group by data
UNION ALL
SELECT Sum(arrivi),Sum(presenze),('STR')As TipoMov,DATENAME(year,@DallaData1) As Anno,DATENAME(MONTH,data) As Mese
FROM Dbo.Tab_movimenti
WHERE
    Codcomune Between 1 and 91 AND
    Codcategoria IN(11,12) AND
                                   Codnazione NOT IN(901,902) AND
    data BetWeen @DallaData1 AND @AllaData1
group by data
Order by anno,tipomov,MONTH(data)