condition mean min max ZT0-3 18.230825 16.45405 20.0076 ZT4-7 13.4163 13.4163 13.4163 ZT8-11 13.63475 13.63475 13.63475 ZT12-15 0 0 0 ZT16-19 17.2742 17.2742 17.2742 ZT20-23 14.010850000000001 14.010850000000001 14.010850000000001