condition mean min max ZT0-3 4515.399244 4515.399244 4515.399244 ZT4-7 3970.201714 3970.201714 3970.201714 ZT8-11 3685.8796455 3685.8796455 3685.8796455 ZT12-15 4126.7320565 4126.7320565 4126.7320565 ZT16-19 3431.8156755 3431.8156755 3431.8156755 ZT20-23 2769.652893 2769.652893 2769.652893