Registers are used for perfomance optimization. As any optimization it has some side effects. For examle let’s see accumulation register subordinated to recorder. They contain precalculated values which are calculated during document posting. This allows to precalculate automatically totals for periods and make obtaining those values faster comparing to SELECT SUM(…) GROUP BY … construction. But on the other side this data is will remain unchanged if data, which it is calculated based on, is changed. For example when you have found a mistake in tax rates which you set in accounting parameters, to correct calculations after a correct tax rate is set, you need to recalculate and repost all posted documents starting from the tax rate change date.