US President Donald Trump has denied an exposé by The New York Times saying he effectively paid no income tax for most of the past two decades, but experts said the methods it was reported he employed to reduce his bill are commonly used by wealthy property developers to file zero-liability tax returns. Al Jazeera reports that US real estate investors are allowed to deduct approximately 4 percent of the purchase value of their buildings from their rental income each year, even though buildings do not usually drop in value. Experts also said it was not uncommon for wealthy business owners to claim that holiday homes or hobby farms were businesses whose running costs should be offset against other income, or that private jet flights for weekends away were business expenses.