EMS statistics by state/province.
D000552:Ambulances / Q000706:statistics & numerical data; D002170:Canada; D003625:Data Collection; D004631:Emergency Medical Service Communication Systems / Q000706:statistics & numerical data; D004632:Emergency Medical Services / Q000706:statistics & numerical data*; D004634:Emergency Medical Technicians / Q000191:economics*; D012456:Salaries and Fringe Benefits / Q000706:statistics & numerical data*; D014481:United States