condition mean min max ZT0-3 12.27435 12.1127 12.436 ZT4-7 9.015905 9.015905 9.015905 ZT8-11 10.9278 10.9278 10.9278 ZT12-15 0 0 0 ZT16-19 17.2932 17.2932 17.2932 ZT20-23 14.96075 14.96075 14.96075