Autofilter, what controls if the blank rows are filtered off or not?

Here's a good one. Why does the workbook (see attachment) filter off blank rows leaving the worksheet skinny?

I should also mention, I used a macro to add the autofilter. The code used to do this is:

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The attachment contains no macro's, apply a filter and notice how the worksheet becomes skinny...

Solution: The skinny workbook (see attachement) was populated by a macro, the macro populated the data then added the autofilter. By switching the order the problem went away and the worksheet no longer becomes skinny.