condition mean min max ZT0-3 9.690940000000001 9.690940000000001 9.690940000000001 ZT4-7 6.134135000000001 6.134135000000001 6.134135000000001 ZT8-11 9.255535 9.255535 9.255535 ZT12-15 11.6965 11.6965 11.6965 ZT16-19 12.766449999999999 12.766449999999999 12.766449999999999 ZT20-23 10.69265 10.69265 10.69265