condition mean min max ZT0-3 5.376177500000001 5.055575 5.69678 ZT4-7 6.48787 6.48787 6.48787 ZT8-11 6.302675 6.302675 6.302675 ZT12-15 0 0 0 ZT16-19 7.38124 7.38124 7.38124 ZT20-23 6.857015 6.857015 6.857015