Reserve Bank of New Zealand governor Graeme Wheeler has said the Reserve Bank would not currently use a debt-to-income multiple limit if it was in its macroprudential tool kit because the housing market appears to be cooling off.Wheeler said he was still in discussions with Finance Minister Bill English about adding the DTI tool to the Memorandum of Understanding that allows the RBNZ to use various macroprudential tools, including its loan-to-valuation ratio restrictions. English had asked a range of questions about the suitability of using such a DTI tool and the potential risks and consequences, Wheeler said."He asked questions such as 'how would these complement our loan to value ratios, what's the nature of the policy problem that we are trying to address, are there any unintended consequences from DTIs for example, are there issues around measurement of debt and measurement of income (and) who would be affected by DTIs?'" he said, adding he had had a couple of discussions with English and had another one scheduled in a couple of weeks."We should make it clear that at this point it is not our intention, if we had them as an instrument in the MOU, it is not our intention to apply them in this situation. We are seeing the housing market come off to some degree in terms of house price inflation," he said."There's a number of reasons for that. It might be linked to the LVRs themselves, it might also be linked to the fact that bank credit criteria has tightened up. You are seeing banks reluctant to lend."Wheeler pointed to tighter lending requirements for apartment developers and non-resident borrowers."So if you put all those reasons together you are starting to see house price inflation slow. We don't know if that is going to continue. We are looking at that very closely, we are watching the data as one would expect and keep an open mind on it."