The OOTB report that most closely matches this requirement is the "Resource Allocations and Assignments" report. You can review a summary of this report
here.
The only caveat is that the Assignment values that it shows are total usage (ETC + Actuals). Theoretically, periods in the past should only have Actuals and periods in the future should only have ETC's. We do not have any OOTB reports that splits these metrics up.