A letter report issued by the Government Accountability Office with an abstract that begins "Ground ambulance providers' costs per transport for 2010 varied widely. The median cost per transport for the providers in GAO's sample was $429, ranging from $224 to $2,204 per transport. Provider characteristics that affected cost per transport were volume of transports (including both Medicare and non-Medicare transports), intensity of transports (the proportion of Medicare transports that were nonemergency), and the extent to which providers received government subsidies. Higher volume of transports, higher proportions of nonemergency transports, and lower government subsidies were associated with lower costs per transport. Providers reported that personnel cost was the largest cost component in their 2010 total costs and the biggest contributor to increases in their total costs from 2009 to 2010."