Selection conditions

The "Snapshots" group

• The dropdown in the group header (to the right of the "Snapshots" heading; it has no label of its own) sets the history depth: "1 year", "5 years", "10 years", "15 years", "All time" or "Custom" — your own year range in the "From year:" and "To year:" fields with the "Apply" button. "10 years" is selected by default.
• Total snapshots — the minimum total number of snapshots over the selected period, any status codes.
• The status-code grid (200, 301, 302, 404, 500, 502, 503) — each code has two fields: the minimum count of snapshots (the "count" column) and the minimum share of all snapshots (the "%" column). For example, "200 ≥ 80%" means the site worked normally for most of its history.

The "Domain history" group

Five numeric thresholds on the domain's archived history. The top three rows have a single field each; the bottom two are a year range with the shared "from" and "to" columns.

• Domain age · "years, from" — the minimum age in years, counted from the first archived snapshot to the last. Young domains are filtered out.
• Continuity · "years in a row, from" — the minimum number of consecutive years in each of which the domain had snapshots. Filters out domains with a patchy history.
• Max downtime · "months, up to" — the maximum allowed gap: consecutive months without a single snapshot. The only "up to" threshold rather than "from": domains with a longer gap are filtered out.
• 1st snapshot year — the year of the first archived snapshot must fall within the "from" — "to" range.
• Last snapshot year — the year of the last archived snapshot must fall within the "from" — "to" range.