Exclude values from a measure?

I have fact table FactSales that looks like this:

ClientKey      OrderDate     OrderTotal
32             1/1/2020      27.00
25             1/2/2020      80.50
30             1/2/2020      100.40

One of the measures that I see in Excel is "Fact Sales Count", which gives me a count.

I'd like to be able to exclude in Excel rows where [FactSales].[OrderTotal] is greater than 30. The measure would be "Fact Sales Count where greater than 30".

My question: how would I create this measure?

The end-result would be that in Excel I can select if the count includes or excludes rows where FactSales.OrderTotal> 30.