Downtime is the part of running a fleet that is easiest to feel and hardest to state as a number. Tracked as a feeling, it shows up as cars that are missing on a busy day, not as a count of the days lost or of the vehicles that lost them.
This guide sets out three things: a working definition of downtime, a way to count it in vehicle-days for each vehicle, and a simple method for putting a value on the days you could avoid. It uses no industry benchmarks. Every number in the method comes from your own fleet and your own assumptions.
What counts as downtime
A workable definition is this: any day the vehicle was not available to rent and was not rented. The reasons usually fall into four states:
- service
- damage
- transfer
- hold
Which of these states count is your decision, because the definition has to match how you manage the fleet. Whatever you decide, write the definition down and keep it the same from one period to the next, so that the counts can be compared.
Note what the definition leaves out. A day on which the vehicle was available to rent but nobody rented it is not downtime. It is a different problem, and counting it as downtime would mix a question about availability with a question about demand.
Count it in vehicle-days
Downtime should be tracked as vehicle-days, not as a feeling. Each vehicle contributes one vehicle-day for every day it spends in a state you count as downtime. Added up over a year, the count gives your total downtime in vehicle-days. The part of it you judge avoidable is the starting input of the value method below.
The count depends on one habit. Every vehicle that is not currently rentable needs a clear state, so that its days out of the rentable fleet are counted rather than remembered.
Why the count has to be per vehicle
A fleet total tells you how much downtime there is. It does not tell you where it comes from.
Knowing the utilization of the whole fleet is not the same as knowing which cars are dragging it down, and downtime works the same way. The same is true of profit: as a fleet-level number at year end it is a record, while as a per-vehicle number it is something you can act on this month. A downtime count kept vehicle by vehicle points to the cars, and the causes, that deserve attention first.
How to shorten downtime
The aim is simple: get the vehicle back on the road sooner. Three practices work on downtime at its source.
- Preventive schedules by mileage, date or inspection.
- Workshop jobs recorded with parts, labour and cost.
- A clear state for every vehicle that is not currently rentable, shared by the workshop and the people who plan the rentals.
In Renticom, fleet and maintenance covers preventive schedules, workshop jobs with parts, labour and cost, and a clear state for every vehicle that is not currently rentable. Because the workshop and the planner share the same availability, a car in service is never allocated to a booking. Downtime is tracked as vehicle-days. You set which states count as downtime. Downtime and replacement planning are also part of Renticom for owned fleets.
Putting a value on the days you could avoid
Once downtime is counted, a value can be put on the part of it you could avoid with one line of arithmetic.
Downtime value recovered = avoided vehicle-days × contribution per rental day
The method needs three inputs.
- Current avoidable downtime, in vehicle-days per year. Not every day of downtime can be avoided; this input is the part you judge could have been.
- Your own assumption of how much of it you expect to avoid, as a percentage. Avoidable downtime multiplied by this percentage gives the avoided vehicle-days.
- Contribution per rental day, a figure from your own business rather than from a benchmark.
Two rules keep the result credible.
- No default percentage. The reduction is an assumption that you control, and it should be a conservative one. A figure taken from another fleet is no substitute for your own.
- An estimate, not a promise. The result is an estimate for business-case planning, not a guarantee of savings or revenue. It depends on your inputs, your operating model, adoption and your baseline performance.
Where to start
Work in order: definition, count, value. Agree which states count as downtime, give every vehicle that is not rentable a clear state, and count vehicle-days for each vehicle over a period. The value calculation means something only once those days are real.
To see how Renticom handles preventive schedules, workshop jobs and vehicle states, see fleet and maintenance.