Displaying number of item by other items

Hello I’m setting up a collection filter but I’m a bit bogged down on one thing, I want to display the number of items per passenger. Basically, instead of “(15)” I want to display “2” next to “5 passengers” since we can see that on xano there are 2 cars that have the attribute “5passengers”.

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Here’s how it goes:

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Why don’t you count this on the backend?