This chapter aims to find out whether changes in sales of cars were likely to have been caused by changes in hire purchase controls. It investigates quarterly sales of cars to see whether the periods of changing sales coincided with periods when changes in controls were likely to be effective. A slump in the motor industry could be caused not only by the imposition or tightening of hire purchase controls on private purchases of cars, but also by a fall in business investment or a fall in exports. The Board of Trade started inquiries in 1956 and the results are published every month in the Board of Trade Journal. In one important respect the motor industry problem differs from that of cotton. The reasons for the difference between the statistics of new registrations and the production statistics of vehicles intended for the home market are the same as those given for the export statistics.