condition mean min max ZT0-3 8.159285 7.5534300000000005 8.765139999999999 ZT4-7 19.61475 19.61475 19.61475 ZT8-11 12.743649999999999 12.743649999999999 12.743649999999999 ZT12-15 0 0 0 ZT16-19 10.903705 10.903705 10.903705 ZT20-23 9.38265 9.38265 9.38265