Over the last 20 tournaments (2003-2023, adjusted for no 2020),
approximately 60% of Final Four teams have been No. 1 seeds. No. 2 seeds
account for 32%, while seeds No. 5 or lower make up 18%. This suggests a
top-heavy trend where higher seeds consistently advance deep, though lower
seeds occasionally break through.

Since 1985, No. 1 seeds have won 24 of 38 titles (63%), peaking in the
2000s with 8 wins in 10 years (2000-2009). However, parity has increased
recently: only 5 of the last 10 champions (2013-2023) were No. 1 seeds,
with notable exceptions like No. 7 UConn (2014) and No. 8 Villanova (1985).
The 2023 tournament, won by No. 4 UConn, marked a rare Final Four without a
No. 1 seed, hinting at growing unpredictability.

Defining Upsets: An upset is typically considered a win by a team seeded at
least 5 lines below its opponent (e.g., No. 12 over No. 5).
The average tournament sees about 8.5 upsets, with a range from 3 (2007) to
14 (2021, 2022). Recent years show a spike, with 9+ upsets in 9 of the last
13 tournaments (2010-2023).

The 2021-2023 tournaments saw unprecedented chaos: 2021 had 14 upsets, 2022
matched it, and 2023 featured a Final Four with No. 4, two No. 5s, and No.
9 seeds.
This may reflect roster instability from the transfer portal and
one-and-done players.

Early 2025 data (as of February) suggests a return to dominance by top
seeds, with analysts noting historical metrics favoring teams like UConn
and Purdue, though upsets remain a wildcard.