condition mean min max ZT0-3 3.8607493087500004 2.9668566075000005 4.75464201 ZT4-7 7.552324708499999 2.4634608085 12.641188608499998 ZT8-11 27.1867965125 23.53817964 30.835413385 ZT12-15 16.440771303 13.727797470999999 19.153745135 ZT16-19 10.95240393175 9.9708271835 11.93398068 ZT20-23 15.366523009999998 14.12952454 16.603521479999998