condition mean min max ZT0-3 6.712870000000001 6.712870000000001 6.712870000000001 ZT4-7 7.133255 7.133255 7.133255 ZT8-11 7.279865 7.279865 7.279865 ZT12-15 6.228 6.228 6.228 ZT16-19 7.28954 7.28954 7.28954 ZT20-23 7.14937 7.14937 7.14937