condition mean min max ZT0-3 5.8428675000000005 5.35035 6.3353850000000005 ZT4-7 6.20336 6.20336 6.20336 ZT8-11 11.49435 11.49435 11.49435 ZT12-15 0 0 0 ZT16-19 8.792785 8.792785 8.792785 ZT20-23 8.3739 8.3739 8.3739