condition mean min max ZT0-3 4.900505 4.900505 4.900505 ZT4-7 2.3259749999999997 2.3259749999999997 2.3259749999999997 ZT8-11 3.5187850000000003 3.5187850000000003 3.5187850000000003 ZT12-15 6.06065 6.06065 6.06065 ZT16-19 6.868315 6.868315 6.868315 ZT20-23 5.614365 5.614365 5.614365