condition mean min max ZT0-3 15.038 14.70805 15.36795 ZT4-7 6.92499 6.92499 6.92499 ZT8-11 8.10277 8.10277 8.10277 ZT12-15 0 0 0 ZT16-19 12.91415 12.91415 12.91415 ZT20-23 11.3352 11.3352 11.3352