condition mean min max ZT0-3 9.668262 9.668262 9.668262 ZT4-7 9.496016000000001 9.496016000000001 9.496016000000001 ZT8-11 10.019395 10.019395 10.019395 ZT12-15 11.778906500000002 11.778906500000002 11.778906500000002 ZT16-19 10.225462 10.225462 10.225462 ZT20-23 8.7881075 8.7881075 8.7881075