The company I work for is in the entertainment business and we have a large set of cars assigned to track and off-track activities. Some of these cars are specific for racing activities are others are just tuned road certified cars. The process of maintaining these cars in a good operating condition involves a series of periodic general inspection, regular change of parts and oil and fuel filling not to mention the inventory of parts which accounts for the largest percentage of money spent on all. Expenses of which the company dedicates a substantial amount of money under the category of cost of doing business.

Our operations department utilizes control charts as an indicator if something is going wrong. One of the variables they focus on is fuel consumption. What was really interesting to me is how specific the process of putting control charts was. The process involved factors like the type of the car, the weather conditions it operates in and the car depreciation value which relates to its usable lifetime. Each one of those affected the level of consumption and it happens that we get a reading for one of the cars beyond the control limits that will indicate that there something wrong with the car and it has to be inspected. Other control charts are prepared in the same manner for the other variables affecting the condition of the car.

As per our operations director, gathering the right set of data is the most difficult part. You will be able to obtain most of the consumption and car wear and tear variables as per industry standards or from the manufacturers themselves. One of the common mistakes is that you will base all of your charts based on them. You will have to collect your own and have a variance analysis just to make sure that you do not get misleading results at the end of the day.