condition mean min max ZT0-3 4.580095 2.916585 5.908474999999999 ZT4-7 2.60395 2.60395 2.60395 ZT8-11 2.6486099999999997 2.6486099999999997 2.6486099999999997 ZT12-15 6.05853 5.746840000000001 6.37022 ZT16-19 5.800409999999999 5.800409999999999 5.800409999999999 ZT20-23 7.26234 7.26234 7.26234