Battle Group (CVBG) is larger than strike group (CSG)

CVBG: 1 carrier, 1 cruiser, 1 cruiser, 2 destroyers, 1 frigate, 2 submarines, and 1 supply ship

CSG: 1 carrier, 1 cruiser, 2 (destroyer/frigate), optional 1 submarine

The introduction of CSG is due to the resource constrain (manpower, navy vessels, and the reduced naval budget)