condition mean min max ZT0-3 9.703067 9.703067 9.703067 ZT4-7 8.822851499999999 8.822851499999999 8.822851499999999 ZT8-11 10.165103 10.165103 10.165103 ZT12-15 8.9182215 8.9182215 8.9182215 ZT16-19 9.078475 9.078475 9.078475 ZT20-23 10.0397 10.0397 10.0397