condition mean min max ZT0-3 10.317018 10.317018 10.317018 ZT4-7 10.1021395 10.1021395 10.1021395 ZT8-11 8.8042485 8.8042485 8.8042485 ZT12-15 9.5989325 9.5989325 9.5989325 ZT16-19 10.711145 10.711145 10.711145 ZT20-23 9.628126 9.628126 9.628126