condition mean min max ZT0-3 10.592543 10.592543 10.592543 ZT4-7 11.861608 11.861608 11.861608 ZT8-11 10.4919275 10.4919275 10.4919275 ZT12-15 10.000521500000001 10.000521500000001 10.000521500000001 ZT16-19 10.063091499999999 10.063091499999999 10.063091499999999 ZT20-23 10.280628499999999 10.280628499999999 10.280628499999999