If Total is a row level calculation e.g. reference to a column in your data and you're using the calculated field as an aggregate e.g. SUM(IIF([Total] !=0, [Total]/[Total],0)) what it will do is to first compute total/total which is 1. then sum up those 1s hence giving your more than 100%.
If you aggregate upfront e.g.
SUM(IIF(SUM([Total]) !=0, SUM([Total])/SUM([Total]),0))
then you should get 100% as expected.
This worked. Thank you
From: Bora Beran
Sent: Monday, February 08, 2016 6:26 PM
To: Daniel Katz <email@example.com>
Subject: Re: - Why are my percentages not calculating correctly?
Tableau Support Community
Why are my percentages not calculating correctly?
reply from Bora Beran
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