Use the AVERAGE() function to calculate a sample average

Hi, I have a sample (attached) to calculate its average. The formula I used initially was:

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The result is 0.62%, which is in fact wrong.

I then amended the formula as:

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The result is 0.83%, which is correct.

I did a few tests and could not see why the first formula is wrong.

Another formula below also confirms that the result from the second formula:

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I've found the answer below using more tests

When the range specified in an array formula (e.g. A1:A200) exceeds the actual data area (e.g. up to row 183), then Excel tries to use numeric value 0 to fill in the cells beyond the actual data area.