condition mean min max ZT0-3 10.831714999999999 8.99308 12.67035 ZT4-7 4.476285 4.476285 4.476285 ZT8-11 3.7389099999999997 3.7389099999999997 3.7389099999999997 ZT12-15 0 0 0 ZT16-19 6.2281949999999995 6.2281949999999995 6.2281949999999995 ZT20-23 8.915325 8.915325 8.915325