OK, to preface this...  I'm not a CPA and my area of experience in regards to taxes is more on the corporation side...   But with that said, let's consider this:

 

A charitable contribution can be taken up to 10% of your income and be used as a deduction to reduce your income tax liability. However, the charitable contribution deduction can only be taken so long as your taxable income nets out to be a positive value.

 

So here's my theory:

 

Based on the information we have regarding his close to 1 billion dollar losses, I think it would come out that trump did not give any charitable contributions because it did not benefit him to do so.

 

I have not heard anyone else say or mention this.  This is just my theory.  I think it might be a reason why he's not releasing his taxes. It would be quite embarrassing if his taxes showed he had no charitable contributions.    

 

 

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