GEOList Summary: Funding Operating Reserve

I’m curious if anyone has had the experience of awarding a grant that includes funds specifically designated for an organization’s operating reserves (i.e., X$ of the grant would be for program support and X$ would go toward operating reserves). If so, how did you structure the grant (e.g., did you stipulate that the funds designated for the operating reserves could not be used for operating expenses for a certain number of years?) and what considerations did you take into account when deciding how much to designate for operating reserves?