Question 1019618
A1=4638.40
A2=(0.75*A1), which is 25% less than 4638.40
A3=(0.75*A2), etc.
There are more elegant ways to do this, but it will work, EXCEPT it never become negative.  It will become 0 to some number of decimal places, and you can't subtract 25% of 0 and get a negative difference. Perhaps if this were 2,5%, it would be close to zero ($76.75) after 162 iterations. 
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