condition mean min max ZT0-3 193.896628 193.896628 193.896628 ZT4-7 256.782461 256.782461 256.782461 ZT8-11 136.6298655 136.6298655 136.6298655 ZT12-15 65.94604799999999 65.94604799999999 65.94604799999999 ZT16-19 23.600072 23.600072 23.600072 ZT20-23 11.413475 11.413475 11.413475