condition mean min max ZT0-3 4.762395 4.762395 4.762395 ZT4-7 4.6106549999999995 4.6106549999999995 4.6106549999999995 ZT8-11 3.54056 3.54056 3.54056 ZT12-15 3.0387500000000003 3.0387500000000003 3.0387500000000003 ZT16-19 3.128615 3.128615 3.128615 ZT20-23 3.754495 3.754495 3.754495