@suzyQ7 It is confusing but to answer your question, no they are not the same. User percentile national is your user percent based on your psat score (cr/w + math). SI percentile is the percent range your SI index fell in.
To further demonstrate that they are two different things, the boy who made a 207 and 99 percent SI percentile, only had a 1320 total psat score but reading/writing was much higher than math and since it counts 2/3, thus the higher SI index. His PSAT user percentile index on his score report is 98%, but his SI index is 99%, of course to account for his SI is stronger than his psat score since his reading/writing counted mre, and in his total psat score R/W counts equal to math. i think for NMSF SI percentile is the one to be concerned with, and that is on your GC’s page.