condition mean min max ZT0-3 5.54819 5.54819 5.54819 ZT4-7 5.6161200000000004 5.6161200000000004 5.6161200000000004 ZT8-11 9.224705 9.224705 9.224705 ZT12-15 12.7697 12.7697 12.7697 ZT16-19 11.112403333333333 11.112403333333333 11.112403333333333 ZT20-23 8.101569999999999 8.101569999999999 8.101569999999999