condition mean min max ZT0-3 11.802574 11.802574 11.802574 ZT4-7 10.428386 10.428386 10.428386 ZT8-11 10.663246 10.663246 10.663246 ZT12-15 10.072678 10.072678 10.072678 ZT16-19 10.3242495 10.3242495 10.3242495 ZT20-23 11.64758 11.64758 11.64758