President Trump's charitable foundation received nearly $2.9 million in contributions in 2016, its latest federal tax filing shows — a million dollars more than it raised in the previous three years combined.

Three donors gave the Donald J. Trump Foundation more than 80 percent of its 2016 contributions. Million-dollar donations came from Las Vegas casino owner Phil Ruffin, a friend of Trump's, and Laura Perlmutter, a Trump family friend and big donor to Republican causes. Ivanka Trump gave $100,000. There's no record of any funds from Trump himself.

The foundation was extraordinarily active in 2016, which included the Republican presidential primaries and the general election. It distributed more than $3 million in grants and contributions, 25 percent more than the total for the preceding three years. The foundation was also busy cleaning up problems in the way it made donations, as documented in a procession of stories by Washington Post reporter David Fahrenthold.

Trump announced in December 2016 he would close the foundation, "to avoid even the appearance of any conflict of interest." But he was blocked by New York State Attorney General Eric Schneiderman, who had started investigating the foundation almost three months earlier for raising money in New York without registering as a charity there.

State law prevents charities under investigation from shutting their doors. "Our investigation into the Donald J. Trump Foundation remains ongoing," Schneiderman's press secretary, Amy Spitalnick, said Monday. "It cannot legally dissolve until that investigation is complete."

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