condition mean min max ZT0-3 9.771635 9.771635 9.771635 ZT4-7 10.008684500000001 10.008684500000001 10.008684500000001 ZT8-11 10.4186205 10.4186205 10.4186205 ZT12-15 11.347243 11.347243 11.347243 ZT16-19 11.302758 11.302758 11.302758 ZT20-23 12.1499725 12.1499725 12.1499725