condition mean min max ZT0-3 15.17275 15.17275 15.17275 ZT4-7 12.2368 12.2368 12.2368 ZT8-11 11.16095 11.16095 11.16095 ZT12-15 10.93075 10.93075 10.93075 ZT16-19 12.2181 12.2181 12.2181 ZT20-23 12.7874 12.7874 12.7874