Cumberland County continues to wear the crown of fastest-growing county in Pennsylvania. Southcentral and southeastern counties remain the bright spots in an aging Pennsylvania. Population has fallen this decade in 47 of the state's 67 counties, but overall it has increased slightly, reaching 12.8 million residents, up 0.8 percent since 2010. In addition to Cumberland, Centre and Lehigh counties, Lebanon and Lancaster counties also are growing. The two were fourth and fifth among counties for percentage growth. Lebanon County's population grew by 4.6 percent since 2010, while Lancaster County's population jumped by 4.5 percent.