If Trump had simply taken his inheritance from daddy and invested it in an S&P Index fund, he'd likely be as rich as he pretends to be on TV. 

FORBES: 1999 Rank: 145; $1.6 billion. Forbes explains: “We love Donald. He returns our calls. He usually pays for lunch. He even estimates his own net worth ($4.5 billion). But no matter how hard we try, we just can’t prove it.”

FORBES: 2000 Rank: 167; $1.7 billion. Forbes explains: “In the Donald’s world, worth more than $5 billion. Back on earth, worth considerably less.”

I'm sure he's hiding his tax returns because he's such an amazing business success! He doesn't want people to find out that he's actually much richer than he makes up, and gives as much to charity as he brags he does. He's just so modest, and as honest as the day is long.