condition mean min max ZT0-3 426.30447 426.30447 426.30447 ZT4-7 239.5751835 239.5751835 239.5751835 ZT8-11 235.2516045 235.2516045 235.2516045 ZT12-15 313.47001950000003 313.47001950000003 313.47001950000003 ZT16-19 516.852614 516.852614 516.852614 ZT20-23 494.102398 494.102398 494.102398