the first election year in which a woman wins the presidential election in the U.S.

Note that in the event of a delayed election - e.g. the 2028 election being pushed to early 2029 instead - then the election still counts as being in the year it was originally scheduled for.

Any presidential candidate who openly and sincerely identifies as a woman counts for the purposes of this question. Nonbinary candidates would not count unless they actively referred to themselves as a woman in addition to being nonbinary.

(UPDATE:) In the event that a party's presidential nominee (as selected at the party convention) is not a woman, but the vice-presidential nominee is, and the party's presidential nominee dies or drops out of the race 

 then this market resolves YES for the year in question 

the party's candidate (the ex-VP-candidate) wins the election.

If the presidential election of 2048 is over, and a woman has not been elected President, this market resolves to "Not before 2052" on the assumption that the next presidential election will happen on schedule.

If the U.S. dissolves entirely at any point between market creation and November 1, 2048, this market resolves as "Not before 2052." It also resolves as "Not before 2052" if the U.S. absolishes the presidency (e.g. in favor of a parliamentary system) and has not re-established the position as of 2049.