condition mean min max ZT0-3 2.4828625 2.471695 2.49403 ZT4-7 3.011335 3.011335 3.011335 ZT8-11 4.54594 4.54594 4.54594 ZT12-15 0 0 0 ZT16-19 4.27072 4.27072 4.27072 ZT20-23 3.020205 3.020205 3.020205