condition mean min max ZT0-3 6.193197635 4.332162014 8.054233256 ZT4-7 7.110326613250001 6.637616466500001 7.583036760000001 ZT8-11 7.449633084 6.2519564475 8.647309720500001 ZT12-15 9.535845322 9.2006707295 9.8710199145 ZT16-19 12.00636910825 9.465394856500001 14.54734336 ZT20-23 30.445744522500004 22.820757710000002 38.070731335000005