How to get the perfromamce for a special calendar week

Hello friends,

I am using Amibroker and I want to do an Exploration for a Special calendar week in history. For example Performance from Gold in US-Dollar in calendar week 13 each year.

I know how to do Exploration with "Day of Week" or "Monthfunction" and I know how to explore tradingday of the year.

But I think calendar week is more complex. Any ideas how to do? Or is this afl still available?

Thanks in advance for your helping Hands.