condition mean min max ZT0-3 195.674571 195.674571 195.674571 ZT4-7 236.7567535 236.7567535 236.7567535 ZT8-11 300.6848645 300.6848645 300.6848645 ZT12-15 342.4903275 342.4903275 342.4903275 ZT16-19 275.583984 275.583984 275.583984 ZT20-23 264.993231 264.993231 264.993231