“Nanofiche can also store up to 2,000 analog pages of text at 150 dpi, per square centimeter. For example a 20 x 20 mm nickel Nanofiche sheet can hold up to 8,000 pages of text rendered at 150 dpi.”
Nickel film holds 2,000 analog pages per square centimeter, no file format required. The Arch Mission projects 50 million years on the Moon and at least 10,000 on Earth. Every claim on the page comes from the foundation that picked it, trademarked the name and sells the vision. The format outlasting us is the easy part. Somebody still has to find the sheet and read English.