condition mean min max ZT0-3 18505.800000000003 18505.800000000003 18505.800000000003 ZT4-7 19506.7 19506.7 19506.7 ZT8-11 19369.800000000003 19369.800000000003 19369.800000000003 ZT12-15 19192.15 19192.15 19192.15 ZT16-19 18108.4 18108.4 18108.4 ZT20-23 17542.65 17542.65 17542.65