condition mean min max ZT0-3 12.118447 12.118447 12.118447 ZT4-7 12.130353 12.130353 12.130353 ZT8-11 12.0002325 12.0002325 12.0002325 ZT12-15 11.86413 11.86413 11.86413 ZT16-19 11.987748499999999 11.987748499999999 11.987748499999999 ZT20-23 13.1595105 13.1595105 13.1595105