Purpose

The Fuel Usage Exception Report is designed to highlight abnormal or suspicious fuel usage across the resources in your fleet

A fuel period (the time span between two fuel fill-ups) will be flagged as an exception (or outlier) if the type of fuel used, or the fuel economy of the resource, lies outside the range of expected values

How the report works

When the report is run, all fuel periods from the selected resources that occur within the selected date range are retrieved and analysed

Each fuel period from each resource is then compared not only against the other fuel periods for that resource, but also against all other fuel periods from the other resources

Using statistical analysis, individual fuel periods are then marked as 'exceptions' if they differ significantly from the rest of the periods

This makes the report responsive to the usage profile and behavior of your fleet. We don't use any predefined values for what the expected fuel economy should be!

Report Example

Exception Examples

Guidelines and tips

Remember, when your run the report, only the fuel periods for the resources you select, occurring within the date range you select, are used for analysis

Therefore, for best results:

• Each time the report is run, select only resources that drive or fuel up in a similar manner
  
  • Perhaps run the report initially for all the heavy trucks, then again later for the white fleet or light vehicles
• For improved accuracy of results, select the largest time period possible
  • This gives the report more data to work with, in order to determine the typical fuel usage
• Exclude resources which experience a wide variety of different usage profiles
• You may find that some fuel periods just slip past the range of expected values
  • Due to the nature of statistics, this will always be the case! Even if the analysis is tweaked to widen the range just a bit.
• Use your own discretion and judgement when acting upon any exceptions found
  • A detailed breakdown of each fuel period for a Resource can be found in the Fuel Period Report
  • You may also find it useful to look at the Trip, Idle and Daily Usage Reports, in order to pin-point the causes of poor fuel economy

The fine print

The statistical method used to identify outliers is the Inter Quartile Range (IQR), also known as the Inter Quartile Fence

The IQR for 'Litres Per Km' and 'Litres Per Engine On Hours' is calculated for each resource, and for the collection of resources in the report as a whole

Each fuel period is checked to determine if it lies outside the IQR for both its resource, then for the collection of resources

If a fuel period is first detected as having a low trip count, or using a different fuel type than expected, then it will not be checked against the IQRs

If a fuel period is outside the range for both the 'Litres Per Km' and 'Litres Per Engine On Hours' IQR, only the 'Litres Per Km' exception is shown