Mean resolution time measures the past. Average ticket age measures the present. It is the indicator that exposes forgotten tickets in the backlog – and almost nobody tracks it.
What it is
Average ticket age is the mean number of days that open tickets have been open, counted from their creation date to today. It does not count closed tickets – it focuses exclusively on what is currently sitting in the queue.
Why it is more revealing than MRT
The Mean Resolution Time (MRT) measures tickets that have already been resolved – naturally the fastest ones pull the average down. Meanwhile, 50 tickets may have been open for 30 days without the MRT showing anything.
Average ticket age exposes exactly those forgotten tickets.
How to calculate it
SQL query for GLPI
-- Average age of open tickets (in days)
SELECT
ROUND(AVG(DATEDIFF(NOW(), date)), 1) AS idade_media_dias,
COUNT(*) AS total_abertos
FROM glpi_tickets
WHERE status NOT IN (5, 6) -- 5=Solved, 6=Closed
AND is_deleted = 0;By group
SELECT
g.completename AS grupo,
ROUND(AVG(DATEDIFF(NOW(), t.date)), 1) AS idade_media,
COUNT(*) AS total
FROM glpi_tickets t
JOIN glpi_groups_tickets gt ON gt.tickets_id = t.id AND gt.type = 2
JOIN glpi_groups g ON g.id = gt.groups_id
WHERE t.status NOT IN (5, 6) AND t.is_deleted = 0
GROUP BY g.completename
ORDER BY idade_media DESC;How to interpret it
| Average age | Interpretation | Action |
|---|---|---|
| < 3 days | Healthy | Maintain |
| 3–7 days | Acceptable | Monitor |
| 7–15 days | Warning | Review backlog, identify bottlenecks |
| > 15 days | Critical | Immediate action: review each old ticket |
Setting up the dashboard
In Metabase or Grafana, create a card with the query above. Add an entity and group filter for drill-down.
A useful complement: a distribution chart showing how many tickets are 0–3 days, 3–7, 7–15 and 15+ days old. This reveals the long tail of the backlog.
Practical action
- Run the query weekly (or automate it in the dashboard)
- If the average age rises, identify the oldest tickets
- Classify them: forgotten (no owner), blocked (waiting on a third party), or legitimate (high complexity)
- For forgotten tickets: reassign. For blocked tickets: document and follow up. For legitimate tickets: review the SLA.
Next step
Combine with the other Service Desk KPIs for a complete view of the operation.
