condition mean min max ZT0-3 388.79999999999995 388.79999999999995 388.79999999999995 ZT4-7 259.4 259.4 259.4 ZT8-11 309.79999999999995 309.79999999999995 309.79999999999995 ZT12-15 281.9 281.9 281.9 ZT16-19 323.6 323.6 323.6 ZT20-23 442.8 442.8 442.8