condition mean min max ZT0-3 3.08912773025 0.668544011 5.5097114495 ZT4-7 9.64438618975 8.572776967 10.7159954125 ZT8-11 7.0316036005 6.496423014 7.566784187 ZT12-15 9.271947998 7.5325319135 11.0113640825 ZT16-19 10.14739703125 9.173607630500001 11.121186431999998 ZT20-23 17.56738064 16.05467531 19.08008597