condition mean min max ZT0-3 11.003475 10.83745 11.1695 ZT4-7 6.997295 6.997295 6.997295 ZT8-11 7.47854 7.47854 7.47854 ZT12-15 0 0 0 ZT16-19 11.37305 11.37305 11.37305 ZT20-23 10.7274 10.7274 10.7274