condition mean min max ZT0-3 15.975154 15.975154 15.975154 ZT4-7 14.784682 14.784682 14.784682 ZT8-11 16.0107155 16.0107155 16.0107155 ZT12-15 17.115023 17.115023 17.115023 ZT16-19 23.458242 23.458242 23.458242 ZT20-23 18.464107499999997 18.464107499999997 18.464107499999997