Before 2016, in which other year did Donald Trump run for President?

The correct answer is that Donald Trump ran for President in 2000. In that year, he campaigned as a candidate for the Reform Party ticket. However, his campaign was short-lived as he withdrew his candidacy early on, citing disagreements with the party's internal dynamics. Although he had expressed interest in running for president before 2016, the 2000 campaign represents the only other year in which he formally entered the race for the presidency.