NEW DELHI: A research report by India's largest bank SBI Wednesday said the rupee depreciation has neither helped in improving exports nor in slowing imports, leading to an incremental trade deficit of USD 4 billion in the first half of the current fiscal.Based on an analysis of both export and import intensive industries during April-September 2018, SBI's report 'Ecowrap' concluded that rupee depreciation has not helped exports as is widely believed."In effect, this means we are having a situation of declining exports and increasing imports. We estimate that the net incremental impact on trade deficit is USD 4 billion."Thus the common refrain that rupee depreciation will lead to export increase and import decline stands challenged," it said.India's exports entered the negative zone after five months, contracting 2.15 per cent in September to USD 27.95 billion due to dip in shipments in key sectors, including engineering and gems and jewellery, even though trade deficit narrowed to a five-month low.Imports in September grew by 10.45 per cent to USD 41.9 billion, according to the commerce ministry data released Monday.The report further said month wise External Commercial Borrowing (ECB) data suggests, during March 2018 to August 2018, industries like petroleum, NBFCs , power, telecommunication and automobile are heavily borrowing through automatic route and aggregately contributing more than 71 per cent of total borrowing."So, any depreciation in rupee will have significant impact on their bottom line if the corporates have not adequately naturalised their risk through hedging," said Ecowrap.