Trying to guess how and when the tax code is going to change and plan for those changes now is an impossible task.

Most prognosticators guessed correctly that President Trump was going to slash the corporate tax rate in 2017. But the doubling of the estate and gift tax exemption to more than $23 million a couple, from an already generous $11 million, was a bit of a surprise. More so was the elimination of deductions for state and local taxes, which disproportionately hit California and states in the Northeast that have high tax rates.

But with a presidential election just a few months away, the game of predicting and analyzing proposals that might affect taxpayers has begun. Most candidates are talking about the big headline-grabbing moves, like health insurance, climate change and infrastructure, as well as the wealth tax that Senators Elizabeth Warren and Bernie Sanders have pitched.

What needs to be analyzed for affluent individuals are the potential changes no candidate is talking about: lowering exemptions and raising rates for the estate and gift taxes and ending the valuation discount for closely held family businesses, a tax break that allows families to transfer a valuable asset for less than it is worth.