That is because in any lower income group, with both an upper and lower bound to the incomes included, the average or mean income will always be much closer to the median.

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In effect, the bank now has a target range for short-term rates: the upper bound is the 1% refi rate and the lower bound is the rate the central bank pays on banks' deposits with it, currently 0.25%.

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My best guess would be that their calculation gives us an upper bound and the actual effect will be above zero but lower than their number.

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