condition mean min max ZT0-3 2.96227 2.96227 2.96227 ZT4-7 2.1197150000000002 2.1197150000000002 2.1197150000000002 ZT8-11 6.289045 6.289045 6.289045 ZT12-15 19.2372 19.2372 19.2372 ZT16-19 14.91695 14.91695 14.91695 ZT20-23 4.886335000000001 4.886335000000001 4.886335000000001