This article provides a clear understanding of the fields Last transition for New Value? and Is Current(New Value)? within the History section on the reports sidebar.
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To find the fields, navigate to Jira Menu → AIO Reports → My Area → My Reports → Open a report/Create report → Sidebar → History section. Look for Last transition for New Value? and Is Current(New Value)? Both the fields work concerning History Old Value and History New Value fields.
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