condition mean min max ZT0-3 8.149719 8.149719 8.149719 ZT4-7 8.556828 8.556828 8.556828 ZT8-11 9.558015000000001 9.558015000000001 9.558015000000001 ZT12-15 10.232296 10.232296 10.232296 ZT16-19 9.188766000000001 9.188766000000001 9.188766000000001 ZT20-23 9.946206499999999 9.946206499999999 9.946206499999999