IGSAs are rated using an overlay of the open end universe (i.e., rated based on their position on the open end fund rating bell curve), not based on Morningstar VA subaccount ratings, nor on the universe of separately managed accounts, collective trusts, and IGSAs.
As mutual funds are oftentimes the underlying investment vehicle in an IGSA and as mutual funds remain a predominant choice for retirement plans, the mutual fund universe provides a robust and appropriate base of comparison for IGSA.