dax

Hello,
On the desktop, I have a slicer which refers to the currency table to pull the currency column.

The slicer has now got a dropdown with all the possible currencies. All good.

Now, I would like to create a measure so that only two currencies are shown i.e. USD, GBP

I have something like the following but it is wrong

Filtered Currencies = calculate(all(Currency), Filter('Currency'[Currency] = "USD" || 'Currency'[Currency] = "GBP"))

Question

What is the DAX to do this measure please?

Thank you