Death and taxes aren’t only certain, they also seem to share a same deadline in the U.S., according to a study that points to the role of stress in fatal accidents. Deaths from traffic accidents around April 15, traditionally the last day to file individual income taxes in the U.S., rose 6 percent on average on each of the last 30 years of tax filing days compared with a day during the week prior and a week later, according to research published in the Journal of the American Medical Association.