What is primarily reported through alternative rollup structures in planning frameworks?

The primary purpose of alternative rollup structures in planning frameworks is to provide flexible reporting of organizational summaries. These rollup structures allow organizations to present data in a way that aligns with their unique business needs and reporting requirements. By leveraging these structures, users can calculate totals from different dimensions and periods, which helps in gaining comprehensive insights into the organization's performance across various segments.

For example, a company might need to summarize financial data at different levels, such as by department, region, or product line. Alternative rollup structures enable this by allowing users to define how data should be aggregated and reported, ensuring that stakeholders can access relevant summaries that facilitate decision-making and strategic planning.

The other options, while relevant to planning and reporting, do not primarily characterize what alternative rollup structures are designed to report. Actuals and forecasts are typically tracked in a more straightforward manner, currency performance pertains to financial analysis involving exchange rates, and dimension attributes are more related to the data elements themselves rather than the aggregated summaries derived from them.