Table 4.

Number of pulmonary computed tomography angiographies performed per 1000 Emergency Department visits within each study period

Month	2008–2009	2012–2013
September	11.74	13.28
October	15.67	7.36
November	13.94	10.08
December	13.43	13.08
January	18.49	10.41
February	16.22	14.25
March	16.92	11.86
April	21.62	13.97
May	18.70	11.72
June	14.71	13.65
July	15.18	17.45
August	11.06	13.33
Average	15.64	12.54