Limit number of Niagara Systems

I have a niagara system that is spawned every time a specific event is called. This event is called quite frequently which results in a large number of niagara systems being spawned, which can be quite performance heavy. Is there a good way of limiting the amount of Niagara systems being spawned in a blueprint? Optimally I would like a max number of about 20 niagara systems being spawned.