condition mean min max ZT0-3 2.9479014494999998 2.231455312 3.664347587 ZT4-7 9.493913509 6.766426823 12.221400195000001 ZT8-11 11.029019401500001 9.589547493000001 12.468491310000001 ZT12-15 7.641456671249999 7.193909035999999 8.0890043065 ZT16-19 15.105029980500001 15.067515356000001 15.142544605000001 ZT20-23 9.34559371425 6.1051982375 12.585989191