First consider an example in which the cutoff value is high enough to include all members:
SELECT MEASURES.[%COUNT] ON 0,
BOTTOMSUM(birthd.decade.MEMBERS, 10000, MEASURES.[%COUNT]) ON 1 FROM patients
Patient Count
1 1910s 71
2 2010s 155
3 1920s 223
4 1930s 572
5 1940s 683
6 1950s 1,030
7 1980s 1,400
8 1990s 1,413
9 2000s 1,433
10 1960s 1,500
11 1970s 1,520
SELECT MEASURES.[%COUNT] ON 0,
BOTTOMSUM(birthd.decade.MEMBERS, 2500, MEASURES.[%COUNT]) ON 1 FROM patients
Patient Count
1 1910s 71
2 2010s 155
3 1920s 223
4 1930s 572
5 1940s 683