condition mean min max ZT0-3 17.61055 15.89 19.3311 ZT4-7 11.43545 11.43545 11.43545 ZT8-11 7.762179999999999 7.762179999999999 7.762179999999999 ZT12-15 0 0 0 ZT16-19 14.4953 14.4953 14.4953 ZT20-23 16.61205 16.61205 16.61205