Just make sure the numerator and denominator are measured over the same timespan.

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Income is the numerator in this fraction but the denominator, too, is changing over time.

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In a fraction, if the denominator drops a lot, the numerator only has to increase a little for the value to go up big.

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Why, you may ask, can't the FPC therefore instruct the banks to leave the denominator alone and simply increase the numerator, by going to their shareholders for more equity capital?

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In essence, this creates an equation in which the variable numerator among coaches, resources, is divided over a constant denominator, wins and losses against the same pool of competition.

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But as I explained above, boosting capital ratios can be achieved either by elevating the numerator - the acquisition of new capital - or by diminishing the denominator, through cutting the provision of loans.

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As it happens, most of the variation in the price of oil over the past 40 years has reflected changes in the value of the dollar (the denominator) rather than the value of oil (the numerator).

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As that denominator is going down those non-income taxes you included in the numerator become more and more significant.

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The analyst is concerned with the growth rate of cash flow (the numerator) and the interest rate by which those cash flows are discounted (the denominator).

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