All of the above.
AWS (AMZN's public cloud reporting segment):
FY15 Revenues: $7.8 billion
CAGR (FY13-FY15): 59%
FY15 Op Margin: 23%
RAX: FY15 Revenues: $2.0 billion
CAGR (FY13-FY15): 14%
FY15 Op Margin: 10%