condition mean min max ZT0-3 78.2972 77.8874 78.707 ZT4-7 33.3545 33.3545 33.3545 ZT8-11 16.09565 16.09565 16.09565 ZT12-15 0 0 0 ZT16-19 43.025000000000006 43.025000000000006 43.025000000000006 ZT20-23 31.669400000000003 31.669400000000003 31.669400000000003