SUICIDES are surging among US soldiers, averaging nearly one a day this year, according to statistics from the country’s defence department.The 154 suicides for active-duty troops in the first 155 days of the year outnumber the US forces killed in action in Afghanistan by about 50 per cent, according to statistics obtained by the Associated Press news agency.The numbers are rising among the 1.4 million active military personnel despite years of effort to encourage troops to seek help with mental health problems.The reasons for the increase are not fully understood. Among explanations, studies have pointed to combat exposure, post-traumatic stress, misuse of prescription medications and personal financial problems.Jackie Garrick, head of a newly established Defence Suicide Prevention Office at the Pentagon, said on Thursday that the suicide numbers this year are troubling."We are very concerned at this point that we are seeing a high number of suicides at a point in time where we were expecting to see a lower number of suicides,” she said, adding that the weak US economy may be confounding preventive efforts even as the pace of military deployments eases.