President Trump signed a $1.5 trillion tax cut in the Oval Office on Dec. 22. The law has become fodder for supporters and detractors alike.

WASHINGTON — The new Republican tax cut is providing a powerful weapon for the law’s supporters and detractors, as well as investors and analysts, who are mining data on how companies are spending their windfalls in a battle to sway the behavior of voters and executives alike.

In the two months since President Trump signed the $1.5 trillion tax bill into law, a vast arsenal of spreadsheets has begun to capture, in real time, the effect of the tax cut as it works its way through corporate balance sheets. Traders are compiling data to find value in a volatile stock market. Advocates of corporate responsibility are hoping to shame companies into passing more of their savings on to employees or charities. Partisans are using it to sway public opinion.

None of the data, as of yet, yield anywhere close to a full picture of how the tax cuts are flowing through corporate boardrooms and into the American economy. But that has not stopped politicians and organizations from using it to advance their goals.

After Congress approved the final version of the tax cut bill, John Kartch, of the conservative-leaning Americans for Tax Reform, started a list that began with AT&T, Comcast and five other companies that had announced wage increases or worker bonuses and credited the moves to the tax cuts. It has since grown to more than 400 companies and emerged as Republicans’ favorite talking point for their new law.

Democrats have been building their own list, of companies announcing stock buybacks, and have showcased that as evidence the bill is benefiting the rich rather than trickling down to workers. Wall Street analysts have since released even more detailed estimates of how companies are responding to the law, which lowered taxes for corporations and so-called pass-through businesses. On Wednesday, the nonprofit research group Just Capital will release one of the most detailed accountings to date: a ranking of companies on how much of their tax windfalls are going to workers, customers, communities and shareholders.

Advocates are hoping that the more information they can bring to the surface, the more they can bend companies’ or voters’ behavior with it.

“What we want to create is sort of a living thing that puts companies on notice,” said Martin Whittaker, chief executive of Just Capital, a nonpartisan group that has compiled data on how 90 public corporations plan to spend their tax savings,…