condition mean min max ZT0-3 12.156908 12.156908 12.156908 ZT4-7 10.878705 10.878705 10.878705 ZT8-11 12.2100045 12.2100045 12.2100045 ZT12-15 12.654679999999999 12.654679999999999 12.654679999999999 ZT16-19 15.845082000000001 15.845082000000001 15.845082000000001 ZT20-23 20.6519755 20.6519755 20.6519755