condition mean min max ZT0-3 13.461505 13.461505 13.461505 ZT4-7 25.1507735 25.1507735 25.1507735 ZT8-11 31.5457435 31.5457435 31.5457435 ZT12-15 19.734392999999997 19.734392999999997 19.734392999999997 ZT16-19 17.2811315 17.2811315 17.2811315 ZT20-23 16.171428 16.171428 16.171428