condition mean min max ZT0-3 195.519257 195.519257 195.519257 ZT4-7 60.2469335 60.2469335 60.2469335 ZT8-11 47.8399315 47.8399315 47.8399315 ZT12-15 52.52538 52.52538 52.52538 ZT16-19 18.084525 18.084525 18.084525 ZT20-23 38.363800499999996 38.363800499999996 38.363800499999996