Macro to Select Drop Down List

Thanks to AB33 I have a working code. But now I need to complicate things.

As you can see from the attached file, my code currently pulls data from the "Data" tab and pastes it into the "Collection_now" tab.
Each time the macro is run it pastes into the next available column.

But the data in "Data" is dependent on the selection from the drop down list in cell B1.
Each time a different value is chosen the values will change in the source range. These formulas don't seem to make sense but this is because I had to simplify them.

Basically I need the macro to choose each selection option in order (1 then 2 then 3), calculate the sheet each time, and paste the values into "Collection_now".
The pasted values should continue to stack on top of each other.

As you can see in the "Collection_needed" tab this is what I want it to look like after that macro has been run.

This is my current code:

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Please let me know if you need any further information.
Thank you in advance for your help!!!

I'm really close with this! Just what part of the code do I need to alter so the Selection 2 pastes beneath Selection 1??

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I figured it out:

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