(CNN) Michael Bloomberg, the former New York mayor who is weighing a 2020 presidential run, is donating $1.8 billion to his alma mater, Johns Hopkins.

The university and Bloomberg are calling it the biggest contribution to an academic institution in American history, according to a press release -- and the gift's record-setting size will not be lost on possible challengers in a Democratic primary. Last week, Bloomberg said he plans to decide on a 2020 bid no later than February , a spokesperson confirmed to CNN.

The gift will fund financial aid for qualified low- and middle-income students, allowing the university to forever make admissions decisions on a "need-blind" basis — without considering an applicant's ability to pay, according to the press release.

The contribution also eliminates student loans from financial aid packages, replacing those loans with grants that don't need to be repaid. The change will ease the burden of student debt for many graduates and make the campus more socioeconomically diverse, Bloomberg wrote in a New York Times op-ed in which he explains his rationale for the gift and the impact it will have.

"America is at its best when we reward people based on the quality of their work, not the size of their pocketbook," he wrote.

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