condition mean min max ZT0-3 6.767580000000001 5.701890000000001 7.833270000000001 ZT4-7 8.259615 8.259615 8.259615 ZT8-11 10.907625 10.907625 10.907625 ZT12-15 0 0 0 ZT16-19 11.478200000000001 11.478200000000001 11.478200000000001 ZT20-23 10.27917 10.27917 10.27917