condition mean min max ZT0-3 268.141524 268.141524 268.141524 ZT4-7 309.65675650000003 309.65675650000003 309.65675650000003 ZT8-11 325.71749 325.71749 325.71749 ZT12-15 330.88055299999996 330.88055299999996 330.88055299999996 ZT16-19 277.90018 277.90018 277.90018 ZT20-23 288.065324 288.065324 288.065324