condition mean min max ZT0-3 8.336659 8.336659 8.336659 ZT4-7 8.033745 8.033745 8.033745 ZT8-11 8.620974499999999 8.620974499999999 8.620974499999999 ZT12-15 8.322675 8.322675 8.322675 ZT16-19 8.260622999999999 8.260622999999999 8.260622999999999 ZT20-23 8.303688999999999 8.303688999999999 8.303688999999999