condition mean min max ZT0-3 1.3873210495 0.541418862 2.233223237 ZT4-7 4.383908881 3.866772493 4.901045269 ZT8-11 7.70294553025 6.033143955 9.3727471055 ZT12-15 9.0326727485 8.814953141 9.250392355999999 ZT16-19 4.31899751825 4.1625467154999996 4.475448321 ZT20-23 2.164155531 1.73812044 2.5901906219999997