condition mean min max ZT0-3 11.167248 11.167248 11.167248 ZT4-7 11.2877315 11.2877315 11.2877315 ZT8-11 11.819195 11.819195 11.819195 ZT12-15 11.607639 11.607639 11.607639 ZT16-19 12.38109 12.38109 12.38109 ZT20-23 12.512718 12.512718 12.512718