condition mean min max ZT0-3 9.78045 9.78045 9.78045 ZT4-7 9.421595 9.421595 9.421595 ZT8-11 6.455615 6.455615 6.455615 ZT12-15 7.55359 7.55359 7.55359 ZT16-19 10.4062 10.4062 10.4062 ZT20-23 9.002455000000001 9.002455000000001 9.002455000000001