condition mean min max ZT0-3 11.9284 11.9284 11.9284 ZT4-7 18.15265 18.15265 18.15265 ZT8-11 12.21895 12.21895 12.21895 ZT12-15 8.37349 8.37349 8.37349 ZT16-19 6.980595 6.980595 6.980595 ZT20-23 9.4282 9.4282 9.4282