en fait voila comment j'ai modifié mais il me fait des crasses.....
SELECT a.type, 100*(B.field/A.field) AS pourcentage
FROM [SELECT type,count(*) AS field FROM requête_lup_2 group by type]. AS A, [SELECT type,count(*) AS field FROM requête_lup_2 WHERE avancement = "100%"]. AS B
GROUP BY 100*(B.field/A.field), a.type;