You mean like the number of cars that passed you? Someone could probably write in IQ app since the Varia can trigger the watch. Out of curiosity, what is your interest in that stat?
I do have the possibility to analyse the datas. I use the varia radar with my mobile phone and app IPBIKE. I have on my screen the speed of the car ,distance, time to reach me and, number of cars. at the end of the ride I have this information in the csv file that can be generated