condition mean min max ZT0-3 9.490118333333333 7.171725 12.02365 ZT4-7 4.902735 4.902735 4.902735 ZT8-11 5.15743 5.15743 5.15743 ZT12-15 6.987275 6.211 7.76355 ZT16-19 4.77471 4.77471 4.77471 ZT20-23 7.77247 7.77247 7.77247