In 2010,a total of 2468435 deaths occurred in the United States. The first two main causes of death, heart disease (597689 deaths) and cancer (574743), and accounted for nearly 50% of all deaths. In contrast,the other main causes accounted for much smaller percentages, ranging from 5.6% (138080 deaths) for the third main cause of death, or chronic lower respiratory disease,to 1.6% (38364) for suicide, the 10th main cause of death. All other causes combined accounted for 25% of the deaths.
Source: cdc.gov