condition mean min max ZT0-3 4.44398 4.44398 4.44398 ZT4-7 2.9843450000000002 2.9843450000000002 2.9843450000000002 ZT8-11 3.6655699999999998 3.6655699999999998 3.6655699999999998 ZT12-15 4.632825 4.632825 4.632825 ZT16-19 5.96836 5.96836 5.96836 ZT20-23 4.36881 4.36881 4.36881