Information about how many emergency response vehicles were available to each English ambulance service trust in 2010, 2011, 2012 and 2013 is not held centrally. Decision making regarding the number of emergency response vehicles is an operational issue and is therefore a matter for the local ambulance trust. No assessment has been made of the proportion of requests for ambulance attendance made by police officers and members of the public which were not fulfilled due to non-availability of vehicles in the last year.