condition mean min max ZT0-3 152.336749 152.336749 152.336749 ZT4-7 183.4845565 183.4845565 183.4845565 ZT8-11 171.1166725 171.1166725 171.1166725 ZT12-15 153.55931450000003 153.55931450000003 153.55931450000003 ZT16-19 150.5694615 150.5694615 150.5694615 ZT20-23 121.15006550000001 121.15006550000001 121.15006550000001