condition mean min max ZT0-3 184.554633 184.554633 184.554633 ZT4-7 122.681467 122.681467 122.681467 ZT8-11 93.941237 93.941237 93.941237 ZT12-15 138.452297 138.452297 138.452297 ZT16-19 156.92453749999999 156.92453749999999 156.92453749999999 ZT20-23 188.7208625 188.7208625 188.7208625