condition mean min max ZT0-3 5.72822334425 5.563473049 5.8929736395 ZT4-7 5.914132086 5.271287813500001 6.5569763585 ZT8-11 6.5835690485 6.137244354 7.029893743000001 ZT12-15 5.72031335 5.4821983375 5.9584283625 ZT16-19 5.352750262500001 4.67832998 6.027170545000001 ZT20-23 11.014943998 9.904523666 12.12536433