0 - 3 of 3 tags for percent

I am trying to get the top 20% of a larger grouping of items;
For example

Why does my percentage have no values after the decimal?

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GOOD    BAD MY_PERCENT  DESIRED_RESULT

Hello,

I am really missing something here, and I hope someone can help me. I am simply trying to divide two numbers, and end up with a percentage. All I get as a result is 1.0000000

Here is the code I am trying to run:

Select Cast(Field1 / Field2 as Decimal (9,8))