Vehicle aging and days in stock: how to read the numbers
7 min readUpdated 2026-08-25
For used-car managers who want a repeatable weekly aging review instead of a gut-feel walk of the lot.
What days in stock actually measures
Days in stock is the number of calendar days between the date a unit was acquired and today (or, for sold units, the delivery date). It is not the same as days on the website: a car can sit in reconditioning for three weeks before a single photo is taken, and those weeks are the most expensive part of its life because nobody can buy it.
Measure from acquisition, not from the day the unit went front-line. If you measure from front-line, recon delays disappear from the report — which is exactly the problem you are trying to see.
The four aging bands
Most retail operations get everything they need from four bands. The point of a band is not the label, it is the action attached to it.
| Band | Days in stock | What it means | Action |
|---|---|---|---|
| Fresh | 0–30 | Inside the highest-margin window | Hold price, maximise exposure |
| Watch | 31–45 | Turn rate is slipping | Re-shoot photos, review description |
| Aged | 46–60 | Margin is being eaten by carrying cost | Market-based price move |
| Distressed | 60+ | Retail exit is unlikely at this price | Wholesale or decisive reprice |
What a day of aging costs you
Carrying cost is floorplan interest plus insurance, plus lot and admin overhead allocated per unit, plus market depreciation. Depreciation is usually the biggest component and the one people forget, because it never appears on an invoice.
Work out your own per-day figure and put it on the aging report. A price reduction stops looking like lost gross once it is compared against the cost of another thirty days.
- Floorplan interest: outstanding advance x rate / 365
- Insurance, lot, detail and admin: monthly overhead / average units on ground / 30
- Market depreciation: your segment's typical monthly decline, divided by 30
The weekly aging review
Book forty-five minutes a week with the same people and the same list. Sort by days in stock descending and start at the oldest unit — the ones that hurt are always at the top.
- Every unit over 45 days gets a decision, not a discussion: reprice, re-merchandise, or wholesale.
- No unit leaves the meeting without an owner and a date.
- Record why. Next quarter's buying gets better only if you can see which sources produced the aged units.
- Track average days in stock by buyer and by source, not just for the lot as a whole.
How Starcar handles it
Starcar stamps acquisition date on every unit, shows the aging band on the inventory list and vehicle detail page, and feeds the same figures into the pricing actions queue, so aged units surface as tasks instead of waiting for someone to notice. Every report exports to CSV, so the numbers are yours whether you stay or leave.
Frequently asked questions
- Should days in stock start at acquisition or at front-line?
- At acquisition. Starting the clock at front-line hides reconditioning delays, which are usually the most expensive and most fixable part of the cycle.
- What is a good average days in stock for used vehicles?
- Most retail operations aim for an average in the 30–45 day range, but the right target depends on your segment and price band. Track your own trend line rather than chasing a benchmark.
- How often should aged units be repriced?
- Give every unit past your watch band a decision at least weekly. Small, frequent moves preserve more gross than one large cut after 90 days.