reason is that the cpi is the measure of inflation most familiar and relevant to canadians. choosing a well - known indicator as a target makes it easier to explain our actions and to be accountable. second, why do we have a range? this is because there are some components of the cpi - such as some energy and food items - whose prices tend to move a lot, both up and down. these movements can cause large fluctuations in the index. if we tried to target inflation too precisely, we would then be adjusting our policy interest rate sharply and frequently, which would lead to greater instability in the economy. having a range reflects the inherent volatility of the cpi. but to be clear, the range is not a zone of indifference - we do aim to achieve the 2 per cent target. another concern is that this volatility can obscure the underlying trend of inflation. so for operational purposes, we use a measure of core inflation. this measure strips out eight of the most volatile components of the cpi and the effect of changes in indirect taxes on the rest of the items. in this way, core inflation provides a better forward - looking indicator of the trend of inflation. finally, since today's monetary policy actions only affect future inflation, we needed to choose a time frame in which to achieve our target. from the beginning, we said that if inflation was pushed off target, we would conduct monetary policy so as to return inflation to target over a period of 18 to 24 months. this is because research has suggested that historically it takes 12 to 18 months for changes in interest rates to have most of their impact on output, and 18 to 24 months to have most of their impact on prices. of course, there is always uncertainty about the lags involved, and i'll have more to say about this later on. before i move on, i want to emphasize three points about our inflation - targeting framework. the first is that we operate in a symmetric way, and we make it clear to everyone that we do so. by this, i mean that we worry just as much about inflation falling below target as we do about it rising above target. when the demand for goods and services pushes the canadian economy against the limits of its capacity, and inflation is poised to rise above target, the bank will raise interest rates to cool off the economy. and when the economy is operating below its production capacity, and inflation is poised to fall below target, the bank will lower interest rates to stimulate growth

smaller and less sophisticated market participants are aware of the need to prepare for the new benchmarks and to take active steps to adjust systems, processes and contracts. time is running short. thank you. 1 see the presentation entitled update on quantitative mapping exercise on the ecb ’ s website. 2 see cœure, b. ( 2017 ), asset purchases, financial regulation and repo market activity, speech at the ercc general meeting on “ the repo market : market conditions and operational challenges ”, brussels, 14 november. 3 see financial stability board ( 2018 ), interest rate benchmark reform – overnight risk - free rates and term rates, 12 july. 4 see regulation ( eu ) 2016 / 1011 of the european parliament and of the council of 8 june 2016 on indices used as benchmarks in financial instruments and financial contracts or to measure the performance of investment funds and amending directives 2008 / 48 / ec and 2014 / 17 / eu and regulation ( eu ) no 596 / 2014 ( oj l 171, 29. 6. 2016, p. 1 ). 5 see cœure, b. ( 2018 ), the importance of euro interest rate benchmark reforms, welcome address at the first meeting of the working group on euro risk - free rates, at the ecb, frankfurt am main, 26 february. 6 the published daily figures are based on time - lagged historical time series for the reserve maintenance periods starting 15 march 2017 and cover the period until 31 july 2018. the update of the pre - ester series is done every maintenance period. 7 see also cœure, b. ( 2017 ), policy analysis with big data, speech given at the conference on “ economic and financial regulation in the era of big data ”, organised by the banque de france, paris, 24 november. 8 testing pre - ester data between march 2017 and may 2018 against contingency thresholds shows that concentration rates were sufficiently low to ensure rate robustness. 9 see cœure, b. ( 2018 ), the future of central bank money, speech at the international centre for monetary and banking studies, geneva, 14 may. 10 / 10 bis central bankers'speeches