condition mean min max ZT0-3 7.297225 7.297225 7.297225 ZT4-7 3.9781850000000003 3.9781850000000003 3.9781850000000003 ZT8-11 3.232425 3.232425 3.232425 ZT12-15 5.316375 5.316375 5.316375 ZT16-19 10.105705 10.105705 10.105705 ZT20-23 7.514530000000001 7.514530000000001 7.514530000000001