condition mean min max ZT0-3 65.84465 65.84465 65.84465 ZT4-7 83.87465 83.87465 83.87465 ZT8-11 39.27735 39.27735 39.27735 ZT12-15 34.76235 34.76235 34.76235 ZT16-19 39.416399999999996 39.416399999999996 39.416399999999996 ZT20-23 63.83775 63.83775 63.83775