condition mean min max ZT0-3 11.849768333333333 11.047755 12.643 ZT4-7 2.33121 2.33121 2.33121 ZT8-11 0.481888 0.481888 0.481888 ZT12-15 1.81525625 1.1376725 2.49284 ZT16-19 2.408 2.408 2.408 ZT20-23 6.19872 6.19872 6.19872