Kuttner and Shim (2013) have made a panel study covering 57 countries and stretching across more than three decades, which investigates the effect on debt and housing prices of various tools. According to their study, the tools that appear to have the most obvious effect on debt include the elimination of tax relief on interest payments and the introduction of a mortgage cap. Let us try to estimate what effects these measures would have on our standard households here. Say that the tax relief for mortgages was abolished. Changes to the tax relief are nothing new – at the end of the 1980s, the tax regulations were changed so that tax relief was almost halved for certain groups of households. For the family in Luleå, with loans worth SEK 1.1 million, the loan costs would rise, if they did not adapt their level of indebtedness, by around SEK 1,100 per month, or almost 3 per cent  18  The calculation is based on assumptions of unchanged yield requirements for the banks of 15 per cent, unchanged borrowing costs for the banks and the allocation of the banks’ costs on the basis of risk weights. 8  BIS central bankers’ speeches  of their disposable income. And for the family in Upplands Väsby, the abolition of the tax relief would increase their loan costs by SEK 1,750, or around 4 per cent of their disposable income.
The crisis gave rise to a new policy area – macroprudential policy – which partly works by influencing the volume of credit in the economy, in roughly the same way as monetary policy. To me, it is fairly obvious that these two policy areas need to interact. If monetary policy is to carry out its tasks well, then macroprudential policy must function properly and most likely also vice versa. The crisis also made necessary a monetary policy that was in many leading countries more expansionary than ever before, and which was conducted in ways not previously tested. Given this, the debate that has arisen on international monetary policy spillover effects is perhaps not particularly remarkable. We do not yet know what our final conclusions will be with regard to these two areas. These are a couple of the loose threads that I am not able to tie up here today. However, a certain amount of new thinking will probably be required, both with regard to monetary policy and financial supervision and the regulation of the financial markets – but also concrete  31  See Ostry and Ghosh (2013). 32  A further possibility that I will not take up here, but which has been tested in emerging markets in particular, is to use capital regulation. For a detailed and partly critical review of the efficiency of capital regulation, see Klein (2012). BIS central bankers’ speeches  15  measures.