National Merit Scholars are typically students who scored in the top 1% on the PSAT/NMSQT. That would mean you would need to score at least 1460 on the test on average.
Each year about 1.5 million high school juniors take the test of which only about 16k students qualify as finalists. Ultimately only 7,500 students will receive the coveted honor of National Merit Scholar.
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