condition mean min max ZT0-3 1504.797755 1504.797755 1504.797755 ZT4-7 1253.141294 1253.141294 1253.141294 ZT8-11 1352.468371 1352.468371 1352.468371 ZT12-15 1535.709328 1535.709328 1535.709328 ZT16-19 1775.0873645 1775.0873645 1775.0873645 ZT20-23 1857.044471 1857.044471 1857.044471