condition mean min max ZT0-3 4.9670075 4.739285000000001 5.19473 ZT4-7 4.845079999999999 4.845079999999999 4.845079999999999 ZT8-11 4.072455 4.072455 4.072455 ZT12-15 0 0 0 ZT16-19 6.19904 6.19904 6.19904 ZT20-23 6.010065000000001 6.010065000000001 6.010065000000001