There are many aspects which are performance-relevant and which could be optimized. First of all - do you need really all fields and all time-periods/categories ... in your datamodel? Further you should avoid high cardinality fields and combined key-fields (use autonumber instead) and build a proper datamodel and try to categorize and/or flag those fields which are be used in calculations. See here a few links as a starting point for many others here within the community:
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