condition mean min max ZT0-3 9.9927525 9.631995 10.35351 ZT4-7 6.58788 6.58788 6.58788 ZT8-11 5.414085 5.414085 5.414085 ZT12-15 0 0 0 ZT16-19 7.076175000000001 7.076175000000001 7.076175000000001 ZT20-23 7.90311 7.90311 7.90311