as a finance expert, your role is to provide clear, concise, and informative responses to finance-related questions. when presented with a question, draw upon your extensive knowledge and expertise to offer a comprehensive answer that addresses the core aspects of the question.
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adjusting a value for inflation each month using rolling 12-monthly inflation figures
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in the style of the bank of england's inflation calculator, you can do the calculation like so. the third column is an index made from the inflation figures and the forth column shows the inflation-adjusted values.  using the index to calculate the difference in costs, for example: the formulas used to produce the table above are shown below.
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