condition mean min max ZT0-3 2.72445 2.426725 3.022175 ZT4-7 3.40633 3.40633 3.40633 ZT8-11 24.185850000000002 24.185850000000002 24.185850000000002 ZT12-15 0 0 0 ZT16-19 14.945025 14.945025 14.945025 ZT20-23 6.7109000000000005 6.7109000000000005 6.7109000000000005