condition mean min max ZT0-3 6.246287499999999 5.66644 6.826135 ZT4-7 4.416684999999999 4.416684999999999 4.416684999999999 ZT8-11 3.7229900000000002 3.7229900000000002 3.7229900000000002 ZT12-15 0 0 0 ZT16-19 5.469135 5.469135 5.469135 ZT20-23 6.99705 6.99705 6.99705