In the wake of a House GOP tax bill that cut the mortgage interest deduction taxpayers can deduct interest on from $1.1 million down to $500,000, a Senate version trimmed it by just $100,000 to $1 million.

According to an analysis of both the House and Senate plans from home listing site Zillow shows why: both tax plans nullify the benefits of the mortgage interest deduction for most homeowners by increasing the standard deduction and eliminating deductions for state-and-local income and sales taxes.

Forbes reported that while the House bill would allow up to $10,000 of property taxes on a home to be deducted, the Senate plan allows no property tax deduction at all. These result is that even fewer homeowners would benefit from itemizing and claiming a mortgage interest deduction under the Senate plan than under the House plan.

The Zillow survey found that 44 percent of U.S. homes are worth enough, and carry high enough tax bills, that a new buyer, borrowing 80 percent of the purchase price, would benefit from itemizing.

Moreover, Zillow Chief Economist Skylar Olsen noted that under the House proposal, that level falls to 12 percent and under the Senate plan, it drops even more with only 7 percent of new buyers would get any benefit from deducting mortgage interest.

“While the Senate’s proposed tax bill makes the MID [mortgage interest deduction] whole on paper by raising the cap back to $1 million in deductible interest, champions of the deduction won’t exactly be breathing a sigh of relief, Under the Senate bill, Zillow’s analysis shows that in most places, even fewer households would itemize deductions, meaning an even smaller sliver of homeowners would benefit from the MID, rendering the MID a much more niche tax benefit. That is sure to cause a stir among industries that rely on widespread use of the MID.”

As the law stands now, homeowners can claim as an itemized deduction interest paid on mortgages valued up to $1.1 million used to acquire or improve a first and/or second home. People who build and sell homes have long argued that the tax incentive facilitates homeownership by making it more affordable. The deduction has been around in various forms since the modern federal income tax was instituted in 1894. Liberal groups argue it disproportionately benefits wealthy and white people. Conservative budget hawks say it costs too much–$77 billion last year. It remains popular with taxpayers.

Nevertheless, it has long been popular with taxpayers.

Both the House and Senate versions roughly double the standard deduction. As a result, were the law in effect in 2017, the standard deduction for an individual would jump to $12,000 from $6,350 under current law. For married couples it would go to $24,000 from $12,500.