condition mean min max ZT0-3 573.321359 573.321359 573.321359 ZT4-7 444.7888195 444.7888195 444.7888195 ZT8-11 455.4884005 455.4884005 455.4884005 ZT12-15 498.24272900000005 498.24272900000005 498.24272900000005 ZT16-19 455.64720650000004 455.64720650000004 455.64720650000004 ZT20-23 375.6203675 375.6203675 375.6203675