For each 40,000 pulses from the vehicle speed sensor (VSS). The trip and total odometers will increase by one mile. Speed is determined by dividing the input pulse frequency (in hertz) by 2.2 hertz/mph. The circuit electronics are calibrated the pointer to a location in proportion to the speed input frequency. That is, as the pulse rate increases, the speedometer records it on an analog display. This display may be limited to a maximum of 85 mph or 199 km/h.