Railways unlike other PSUs IR is wholly managed (Rail Ministry) and funded (Union Budget) by GOI. So any funds by the government to the railways is like an equity investment. Like equity, GOI invests in IR , but would only get a return when there is net profit (which IR is not). So, until an unless railways make net profit and is able to fund all its investment plans it won't be able to provide returns to GOI. So for any deficit in revenue and expenditure is funded by the Union Budget. However, IR has pay interest on the borrowed fund from other PSU or GOI will pay for it in case of default. So, in this case GOI is the owner of IR and the guarantor for IR.