condition mean min max ZT0-3 5.9178949415 5.848713326 5.987076557 ZT4-7 6.497873363 6.175839245 6.8199074809999995 ZT8-11 6.5036736875 6.16705335 6.840294025 ZT12-15 6.243568017166666 6.182876028666667 6.3042600056666664 ZT16-19 6.919613833 6.768860190333333 7.070367475666666 ZT20-23 6.8686910885 6.536514775333333 7.200867401666667