condition mean min max ZT0-3 13.679553 13.679553 13.679553 ZT4-7 13.5415115 13.5415115 13.5415115 ZT8-11 14.7407215 14.7407215 14.7407215 ZT12-15 14.3458135 14.3458135 14.3458135 ZT16-19 15.598146499999999 15.598146499999999 15.598146499999999 ZT20-23 13.9097395 13.9097395 13.9097395