condition mean min max ZT0-3 10.141265 10.141265 10.141265 ZT4-7 8.4769535 8.4769535 8.4769535 ZT8-11 8.873145000000001 8.873145000000001 8.873145000000001 ZT12-15 11.661009499999999 11.661009499999999 11.661009499999999 ZT16-19 9.770399999999999 9.770399999999999 9.770399999999999 ZT20-23 9.897102499999999 9.897102499999999 9.897102499999999