Data collection total count

I’d like to know the total count of a data collection after filtering the data. Basically, if I were to filter a data collection, but afterwards wanted to know the total count, is there a way to find out without unfiltering and then refiltering? Please see my snippet below.

https://webix.com/snippet/3034b649

let totalCount = Object.keys($$("datatable").data.pull).length;

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