condition mean min max ZT0-3 0.637328 0.637328 0.637328 ZT4-7 0.4999605 0.4999605 0.4999605 ZT8-11 0.35845150000000003 0.35845150000000003 0.35845150000000003 ZT12-15 0.22964249999999997 0.22964249999999997 0.22964249999999997 ZT16-19 0.47134000000000004 0.47134000000000004 0.47134000000000004 ZT20-23 0.516799 0.516799 0.516799