The average zip rating of placegetters, by the way, is about 52, but 51 and 53 are by far the most common zip numbers in my sample.The numbers fall right off below 50. Virtually no placegetters with zips below 50 - couldn't find a single one below 48. Which is useful to know because there will often be two or three runners below 50 which you can therefore safely eliminate. Very few placegetters with zips over 57. The range is 57-50. A tighter range of 56-51 would still net the vast majority of placegetters.