I run a few seed nodes and here's some stats that might be useful if you want to run a seed node on data usage:
Chicago Seed Node:
monthly
rx | tx | total | avg. rate
------------------------+-------------+-------------+---------------
2024-12 150.79 GiB | 489.10 GiB | 639.89 GiB | 2.05 Mbit/s
2025-01 17.91 GiB | 41.42 GiB | 59.32 GiB | 1.16 Mbit/s
------------------------+-------------+-------------+---------------
estimated 108.82 GiB | 251.73 GiB | 360.55 GiB |
daily
rx | tx | total | avg. rate
------------------------+-------------+-------------+---------------
yesterday 4.23 GiB | 18.78 GiB | 23.01 GiB | 2.29 Mbit/s
today 443.85 MiB | 1.04 GiB | 1.47 GiB | 1.45 Mbit/s
------------------------+-------------+-------------+---------------
estimated 4.30 GiB | 10.32 GiB | 14.62 GiB |
NYC Seed Node:
monthly
rx | tx | total | avg. rate
------------------------+-------------+-------------+---------------
2024-12 225.89 GiB | 739.40 GiB | 965.29 GiB | 3.10 Mbit/s
2025-01 27.96 GiB | 89.84 GiB | 117.80 GiB | 2.30 Mbit/s
------------------------+-------------+-------------+---------------
estimated 169.91 GiB | 546.04 GiB | 715.95 GiB |
daily
rx | tx | total | avg. rate
------------------------+-------------+-------------+---------------
yesterday 6.33 GiB | 26.30 GiB | 32.63 GiB | 3.24 Mbit/s
today 655.13 MiB | 2.76 GiB | 3.40 GiB | 3.36 Mbit/s
------------------------+-------------+-------------+---------------
estimated 6.35 GiB | 27.42 GiB | 33.77 GiB |
But running a witness node will have a lot less tx so it'll be lower.