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17.22. Where it is not possible or necessary to maintain a long time series, an approach of “bridging” the current published estimates and the estimates produced by the revised methodology is used. Bridging means that estimates on both the current and new basis are produced for one point in time and both sets of estimates are released along with analysis to help users understand the differences between the series. The technique is particularly relevant for series where modelling beyond a certain time may not be appropriate.
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